Consolidated Condensed Schedule Of Investments (Long Investments) - USD ($) shares in Thousands		9 Months Ended		12 Months Ended
		Sep. 30, 2018		Dec. 31, 2017
Schedule of Investments [Line Items]
Investments Fair Value		$ 2,670,069,000		$ 2,071,707,000
Investment Owned, at Cost		$ 2,694,223,000		$ 2,071,754,000
Percentage collaterallized by GNRCMO certificates		100.00%		100.00%
Non-performing loans, maturity date not applicable		$ 3,500,000		$ 23,900,000
Mortgage Loans in Process of Foreclosure, Amount		$ 9,300,000		$ 5,200,000
Unrated But Agency-Guaranteed [Member]
Schedule of Investments [Line Items]
Long investment holdings as a percentage of stockholders' equity		202.37%		160.32%
Long Investment Aaa Rating [Member]
Schedule of Investments [Line Items]
Long investment holdings as a percentage of stockholders' equity		0.69%
Long Investment Aa Rating [Member]
Schedule of Investments [Line Items]
Long investment holdings as a percentage of stockholders' equity		0.90%
Long Investment A Rating [Member]
Schedule of Investments [Line Items]
Long investment holdings as a percentage of stockholders' equity		5.98%		0.81%
Long Investment BBB Rating [Member]
Schedule of Investments [Line Items]
Long investment holdings as a percentage of stockholders' equity		6.06%		2.62%
Long Investment BB Rating [Member]
Schedule of Investments [Line Items]
Long investment holdings as a percentage of stockholders' equity		61.53%		68.03%
Long Investment Unrated Rating [Member]
Schedule of Investments [Line Items]
Long investment holdings as a percentage of stockholders' equity		155.45%		101.85%
Related Party-Consumer Loans Titled in Name of Related Party [Member]
Schedule of Investments [Line Items]
Fair value of loans held in related party trust		$ 19,800,000		$ 11,700,000
Purchasing Entity [Member]
Schedule of Investments [Line Items]
Fair value of loans held in related party trust		$ 180,700,000		$ 114,500,000
Principal And Interest - Fixed Rate Agency Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		137.91%	[1],[2],[3],[4]	123.80%	[5],[6],[7],[8]
Investments Fair Value		$ 850,453,000	[1],[3],[4]	$ 768,751,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 4.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 142,232,000	[1],[3],[4]	$ 130,885,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 144,555,000	[1],[3],[4]	$ 138,033,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 4.00% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2039-09	[1],[3],[4]	2039-09	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 4.00% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-09	[1],[3],[4]	2047-11	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Four Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 116,796,000	[1],[3],[4]	$ 115,008,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 118,777,000	[1],[3],[4]	$ 121,154,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Four Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2041-11	[1],[3],[4]	2041-11	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Four Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-09	[1],[3],[4]	2047-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 3.50% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 84,194,000	[1],[3],[4]	$ 77,724,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 83,182,000	[1],[3],[4]	$ 80,245,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 3.50% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2042-09	[1],[3],[4]	2042-09	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 3.50% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-02	[1],[3],[4]	2047-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Four Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 69,656,000	[1],[3],[4]	$ 60,698,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 72,403,000	[1],[3],[4]	$ 65,178,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Four Point Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2041-10	[1],[3],[4]	2041-10	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Four Point Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-09	[1],[3],[4]	2047-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 54,151,000	[1],[3],[4]	$ 42,239,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 55,026,000	[1],[3],[4]	$ 44,414,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.00% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2045-07	[1],[3],[4]	2045-07	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.00% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-05	[1],[3],[4]	2047-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Four Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 46,289,000	[1],[3],[4]	$ 47,555,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 48,076,000	[1],[3],[4]	$ 50,980,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Four Point Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2043-09	[1],[3],[4]	2043-09	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Four Point Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-09	[1],[3],[4]	2047-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount	[1],[3],[4]	$ 44,474,000
Rate	[1],[3],[4]	5.00%
Investments Fair Value	[1],[3],[4]	$ 46,735,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2048-02
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2048-08
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.50% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 44,456,000	[1],[3],[4]	$ 51,851,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 44,747,000	[1],[3],[4]	$ 53,894,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.50% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2028-03	[1],[3],[4]	2028-03	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.50% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2032-03	[1],[3],[4]	2032-03	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 38,966,000	[1],[3],[4]	$ 32,061,000	[5],[7],[8]
Rate		5.00%	[1],[3],[4]	5.00%	[5],[7],[8]
Investments Fair Value		$ 41,243,000	[1],[3],[4]	$ 34,664,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2035-10	[1],[3],[4]	2035-10	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-08	[1],[3],[4]	2044-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Three Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 32,509,000	[1],[3],[4]	$ 33,982,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 32,243,000	[1],[3],[4]	$ 35,235,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Three Point Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2042-12	[1],[3],[4]	2045-07	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Three Point Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2047-02	[1],[3],[4]	2047-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.50% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 30,083,000	[1],[3],[4]	$ 21,561,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 31,271,000	[1],[3],[4]	$ 22,924,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.50% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2046-09	[1],[3],[4]	2046-09	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.50% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-08	[1],[3],[4]	2047-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Three Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 26,297,000	[1],[3],[4]	$ 23,002,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 26,009,000	[1],[3],[4]	$ 23,753,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Three Point Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2042-01	[1],[3],[4]	2042-01	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Three Point Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-03	[1],[3],[4]	2047-09	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 5.50% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount	[1],[3],[4]	$ 15,780,000
Rate	[1],[3],[4]	5.50%
Investments Fair Value	[1],[3],[4]	$ 16,791,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 5.50% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2048-04
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 5.50% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2048-08
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount	[1],[3],[4]	$ 11,259,000
Rate	[1],[3],[4]	3.00%
Investments Fair Value	[1],[3],[4]	$ 11,139,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.00% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2030-04
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.00% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2032-09
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 3.50% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 8,447,000	[1],[3],[4]	$ 9,405,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 8,503,000	[1],[3],[4]	$ 9,764,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 3.50% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2028-09	[1],[3],[4]	2028-09	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 3.50% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2032-12	[1],[3],[4]	2032-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) Three Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 8,136,000	[1],[3],[4]	$ 8,960,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 8,061,000	[1],[3],[4]	$ 9,221,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) Three Point Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2030-02	[1],[3],[4]	2030-02	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) Three Point Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2046-09	[1],[3],[4]	2046-09	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 4.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 6,022,000	[1],[3],[4]	$ 8,156,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 6,138,000	[1],[3],[4]	$ 8,562,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 4.00% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2026-06	[1],[3],[4]	2026-06	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 4.00% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2031-05	[1],[3],[4]	2031-05	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Associatin Pools (Thirty Year) 5.50% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2039-10
Current Principal/Notional Amount		$ 5,048,000	[1],[3],[4]	$ 2,335,000	[5],[7],[8]
Rate		5.50%	[1],[3],[4]	5.50%	[5],[7],[8]
Investments Fair Value		$ 5,419,000	[1],[3],[4]	$ 2,569,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Associatin Pools (Thirty Year) 5.50% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2039-10
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Associatin Pools (Thirty Year) 5.50% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2048-06
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Three Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 5,541,000	[1],[3],[4]	$ 3,519,000	[5],[7],[8]
Rate		3.00%	[1],[3],[4]	3.00%	[5],[7],[8]
Investments Fair Value		$ 5,364,000	[1],[3],[4]	$ 3,547,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Three Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2042-11	[1],[3],[4]	2042-11	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Three Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-05	[1],[3],[4]	2042-12	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) 5.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2044-07
Current Principal/Notional Amount		$ 5,029,000	[1],[3],[4]	$ 488,000	[5],[7],[8]
Rate		5.00%	[1],[3],[4]	5.00%	[5],[7],[8]
Investments Fair Value		$ 5,295,000	[1],[3],[4]	$ 526,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) 5.00% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2044-07
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) 5.00% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2048-04
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 5.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 4,797,000	[1],[3],[4]	$ 5,410,000	[5],[7],[8]
Rate		5.00%	[1],[3],[4]	5.00%	[5],[7],[8]
Investments Fair Value		$ 5,045,000	[1],[3],[4]	$ 5,888,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 5.00% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2043-09	[1],[3],[4]	2043-09	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 5.00% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2044-01	[1],[3],[4]	2044-01	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 4.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2047-12
Current Principal/Notional Amount		$ 4,413,000	[1],[3],[4]	$ 4,981,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 4,446,000	[1],[3],[4]	$ 5,159,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 4.00% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2037-06
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 4.00% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2047-12
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Three Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 2,792,000	[1],[3],[4]	$ 3,579,000	[5],[7],[8]
Rate		3.00%	[1],[3],[4]	3.00%	[5],[7],[8]
Investments Fair Value		$ 2,689,000	[1],[3],[4]	$ 3,587,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Three Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2043-07	[1],[3],[4]	2043-07	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Three Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2045-06	[1],[3],[4]	2045-10	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) 4.50% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2044-05	[1],[3],[4]	2044-05	[5],[7],[8]
Current Principal/Notional Amount		$ 2,524,000	[1],[3],[4]	$ 2,671,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 2,610,000	[1],[3],[4]	$ 2,875,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Three Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 2,639,000	[1],[3],[4]	$ 2,791,000	[5],[7],[8]
Rate		3.00%	[1],[3],[4]	3.00%	[5],[7],[8]
Investments Fair Value		$ 2,543,000	[1],[3],[4]	$ 2,804,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Three Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2042-01	[1],[3],[4]	2042-01	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Three Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2045-06	[1],[3],[4]	2045-06	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 3.75% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2047-07	[1],[3],[4]	2047-07	[5],[7],[8]
Current Principal/Notional Amount		$ 2,519,000	[1],[3],[4]	$ 2,906,000	[5],[7],[8]
Rate		3.75%	[1],[3],[4]	3.75%	[5],[7],[8]
Investments Fair Value		$ 2,517,000	[1],[3],[4]	$ 3,025,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 4.50% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2041-05	[1],[3],[4]	2041-05	[5],[7],[8]
Current Principal/Notional Amount		$ 2,341,000	[1],[3],[4]	$ 2,877,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 2,396,000	[1],[3],[4]	$ 3,021,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Fifteen Year) Four Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2026-04	[1],[3],[4]	2026-04	[5],[7],[8]
Current Principal/Notional Amount		$ 2,313,000	[1],[3],[4]	$ 2,794,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 2,391,000	[1],[3],[4]	$ 2,973,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Fifteen Year) Three Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2030-04
Current Principal/Notional Amount		$ 2,389,000	[1],[3],[4]	$ 3,833,000	[5],[7],[8]
Rate		3.00%	[1],[3],[4]	3.00%	[5],[7],[8]
Investments Fair Value		$ 2,362,000	[1],[3],[4]	$ 3,912,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Fifteen Year) Three Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2030-04
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Fifteen Year) Three Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2032-09
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Five Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 1,757,000	[1],[3],[4]	$ 516,000	[5],[7],[8]
Rate		5.50%	[1],[3],[4]	5.50%	[5],[7],[8]
Investments Fair Value		$ 1,890,000	[1],[3],[4]	$ 565,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Five Point Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2033-08	[1],[3],[4]	2033-08	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Five Point Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2048-05	[1],[3],[4]	2038-11	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Twenty Year) Four Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2033-12	[1],[3],[4]	2033-12	[5],[7],[8]
Current Principal/Notional Amount		$ 1,575,000	[1],[3],[4]	$ 1,633,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 1,612,000	[1],[3],[4]	$ 1,728,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 6.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2048-05
Current Principal/Notional Amount	[1],[3],[4]	$ 1,232,000
Rate	[1],[3],[4]	6.00%
Investments Fair Value	[1],[3],[4]	$ 1,323,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Fifteen Year) Four Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2029-02	[1],[3],[4]	2029-02	[5],[7],[8]
Current Principal/Notional Amount		$ 1,063,000	[1],[3],[4]	$ 1,463,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 1,085,000	[1],[3],[4]	$ 1,531,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) Three Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 1,070,000	[1],[3],[4]	$ 1,175,000	[5],[7],[8]
Rate		3.00%	[1],[3],[4]	3.00%	[5],[7],[8]
Investments Fair Value		$ 1,054,000	[1],[3],[4]	$ 1,193,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) Three Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2028-06	[1],[3],[4]	2028-06	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) Three Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2030-03	[1],[3],[4]	2030-03	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Twenty Year) Four Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2033-12	[1],[3],[4]	2033-12	[5],[7],[8]
Current Principal/Notional Amount		$ 988,000	[1],[3],[4]	$ 1,023,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 1,030,000	[1],[3],[4]	$ 1,099,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Six Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 860,000	[1],[3],[4]	$ 1,207,000	[5],[7],[8]
Rate		6.00%	[1],[3],[4]	6.00%	[5],[7],[8]
Investments Fair Value		$ 929,000	[1],[3],[4]	$ 1,360,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Six Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2039-09	[1],[3],[4]	2039-09	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Six Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2040-02	[1],[3],[4]	2040-02	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Thirty Year) Six Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2040-05	[1],[3],[4]	2040-05	[5],[7],[8]
Current Principal/Notional Amount		$ 851,000	[1],[3],[4]	$ 864,000	[5],[7],[8]
Rate		6.00%	[1],[3],[4]	6.00%	[5],[7],[8]
Investments Fair Value		$ 923,000	[1],[3],[4]	$ 969,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) Three Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2046-10
Current Principal/Notional Amount	[1],[3],[4]	$ 866,000
Rate	[1],[3],[4]	3.00%
Investments Fair Value	[1],[3],[4]	$ 825,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Thirty Year) Two Point Four Nine Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2043-10
Current Principal/Notional Amount	[1],[3],[4]	$ 646,000
Rate	[1],[3],[4]	2.49%
Investments Fair Value	[1],[3],[4]	$ 598,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) Three Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 545,000	[1],[3],[4]	$ 644,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 533,000	[1],[3],[4]	$ 647,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) Three Point Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2030-10	[1],[3],[4]	2030-10	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) Three Point Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2032-02	[1],[3],[4]	2032-02	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) Three Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2026-04	[1],[3],[4]	2026-04	[5],[7],[8]
Current Principal/Notional Amount		$ 430,000	[1],[3],[4]	$ 492,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 433,000	[1],[3],[4]	$ 504,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) Three Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2030-06	[1],[3],[4]	2030-06	[5],[7],[8]
Current Principal/Notional Amount		$ 143,000	[1],[3],[4]	$ 150,000	[5],[7],[8]
Rate		3.00%	[1],[3],[4]	3.00%	[5],[7],[8]
Investments Fair Value		$ 137,000	[1],[3],[4]	$ 150,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Thirty Year) Three Point Two Eight Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2042-06	[1],[3],[4]	2042-06	[5],[7],[8]
Current Principal/Notional Amount		$ 110,000	[1],[3],[4]	$ 112,000	[5],[7],[8]
Rate		3.28%	[1],[3],[4]	3.28%	[5],[7],[8]
Investments Fair Value		$ 105,000	[1],[3],[4]	$ 112,000	[5],[7],[8]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) Three Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount	[5],[7],[8]			$ 20,544,000
Rate	[5],[7],[8]			3.00%
Investments Fair Value	[5],[7],[8]			$ 20,986,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) Three Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2030-04
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) Three Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2032-09
Interest Only - Fixed Rate Agency Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		1.92%	[1],[2],[3],[4]	2.03%	[5],[6],[7],[8]
Investments Fair Value		$ 11,843,000	[1],[3],[4]	$ 12,594,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 4.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 18,398,000	[1],[3],[4]	$ 21,942,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 3,164,000	[1],[3],[4]	$ 3,686,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 4.00% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2045-02	[1],[3],[4]	2045-02	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 4.00% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2045-06	[1],[3],[4]	2045-06	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 4.50% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 11,223,000	[1],[3],[4]	$ 6,286,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 1,450,000	[1],[3],[4]	$ 928,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 4.50% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2020-12	[1],[3],[4]	2020-12	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 4.50% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2044-06	[1],[3],[4]	2044-06	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 6.00% [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 5,000,000	[1],[3],[4]	$ 5,867,000	[5],[7],[8]
Rate		6.00%	[1],[3],[4]	6.00%	[5],[7],[8]
Investments Fair Value		$ 1,050,000	[1],[3],[4]	$ 1,173,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 6.00% [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2038-06	[1],[3],[4]	2038-06	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 6.00% [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2039-08	[1],[3],[4]	2039-08	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Four Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 6,464,000	[1],[3],[4]	$ 5,437,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 902,000	[1],[3],[4]	$ 914,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Four Point Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2039-06	[1],[3],[4]	2041-02	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Four Point Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2044-07	[1],[3],[4]	2044-07	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Five Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2039-10	[1],[3],[4]	2039-10	[5],[7],[8]
Current Principal/Notional Amount		$ 3,554,000	[1],[3],[4]	$ 4,116,000	[5],[7],[8]
Rate		5.50%	[1],[3],[4]	5.50%	[5],[7],[8]
Investments Fair Value		$ 795,000	[1],[3],[4]	$ 907,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Five Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2043-11	[1],[3],[4]	2043-11	[5],[7],[8]
Current Principal/Notional Amount		$ 3,816,000	[1],[3],[4]	$ 4,660,000	[5],[7],[8]
Rate		5.50%	[1],[3],[4]	5.50%	[5],[7],[8]
Investments Fair Value		$ 683,000	[1],[3],[4]	$ 801,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Four Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 3,728,000	[1],[3],[4]	$ 4,185,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 603,000	[1],[3],[4]	$ 521,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Four Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2039-05	[1],[3],[4]	2039-05	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Four Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2043-11	[1],[3],[4]	2043-11	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Three Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2032-12	[1],[3],[4]	2032-12	[5],[7],[8]
Current Principal/Notional Amount		$ 3,807,000	[1],[3],[4]	$ 4,350,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 559,000	[1],[3],[4]	$ 628,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 2,937,000	[1],[3],[4]	$ 4,100,000	[5],[7],[8]
Rate		5.00%	[1],[3],[4]	5.00%	[5],[7],[8]
Investments Fair Value		$ 512,000	[1],[3],[4]	$ 493,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2038-01	[1],[3],[4]	2038-01	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2040-05	[1],[3],[4]	2040-05	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2038-11	[1],[3],[4]	2038-11	[5],[7],[8]
Current Principal/Notional Amount		$ 5,658,000	[1],[3],[4]	$ 7,145,000	[5],[7],[8]
Rate		5.00%	[1],[3],[4]	5.00%	[5],[7],[8]
Investments Fair Value		$ 494,000	[1],[3],[4]	$ 598,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Five Point FIve Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 4,101,000	[1],[3],[4]	$ 5,074,000	[5],[7],[8]
Rate		5.50%	[1],[3],[4]	5.50%	[5],[7],[8]
Investments Fair Value		$ 403,000	[1],[3],[4]	$ 494,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Five Point FIve Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2039-01	[1],[3],[4]	2039-01	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Five Point FIve Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2039-09	[1],[3],[4]	2039-09	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Six Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2040-01	[1],[3],[4]	2040-01	[5],[7],[8]
Current Principal/Notional Amount		$ 1,703,000	[1],[3],[4]	$ 2,038,000	[5],[7],[8]
Rate		6.00%	[1],[3],[4]	6.00%	[5],[7],[8]
Investments Fair Value		$ 301,000	[1],[3],[4]	$ 371,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Four Point Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2043-07	[1],[3],[4]	2043-07	[5],[7],[8]
Current Principal/Notional Amount		$ 1,507,000	[1],[3],[4]	$ 1,699,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 294,000	[1],[3],[4]	$ 256,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2037-05
Current Principal/Notional Amount		$ 3,444,000	[1],[3],[4]	$ 1,168,000	[5],[7],[8]
Rate		5.00%	[1],[3],[4]	5.00%	[5],[7],[8]
Investments Fair Value		$ 228,000	[1],[3],[4]	$ 47,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Five Percent [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2037-05
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Five Percent [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2041-05
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Three Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2041-09	[1],[3],[4]	2041-09	[5],[7],[8]
Current Principal/Notional Amount		$ 2,363,000	[1],[3],[4]	$ 2,677,000	[5],[7],[8]
Rate		3.00%	[1],[3],[4]	3.00%	[5],[7],[8]
Investments Fair Value		$ 225,000	[1],[3],[4]	$ 247,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Four Point Seven Five Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2040-07	[1],[3],[4]	2040-07	[5],[7],[8]
Current Principal/Notional Amount		$ 893,000	[1],[3],[4]	$ 1,000,000	[5],[7],[8]
Rate		4.75%	[1],[3],[4]	4.75%	[5],[7],[8]
Investments Fair Value		$ 180,000	[1],[3],[4]	$ 178,000	[5],[7],[8]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Point Two SIx Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2040-06
Current Principal/Notional Amount	[5],[7],[8]			$ 74,967,000
Rate	[5],[7],[8]			0.26%
Investments Fair Value	[5],[7],[8]			$ 352,000
TBA - Fixed Rate Agency Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		49.22%	[1],[2],[3],[4]	19.92%	[5],[6],[7],[8]
Current Principal/Notional Amount		$ 294,986,000		$ 118,806,000
Investments Fair Value		$ 303,552,000	[1],[3],[4]	$ 123,680,000	[5],[7],[8]
TBA - Fixed Rate Agency Securities [Member] | Government National Mortgage Association (30 Year) 5 Point 00 Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2018-10
Current Principal/Notional Amount	[1],[3],[4]	$ 120,155,000
Rate	[1],[3],[4]	5.00%
Investments Fair Value	[1],[3],[4]	$ 125,444,000
TBA - Fixed Rate Agency Securities [Member] | Government National Mortgage Association (30 Year) 4 Point 50 Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2018-10	[1],[3],[4]	2018-01	[5],[7],[8]
Current Principal/Notional Amount		$ 70,409,000	[1],[3],[4]	$ 35,719,000	[5],[7],[8]
Rate		4.50%	[1],[3],[4]	4.50%	[5],[7],[8]
Investments Fair Value		$ 72,757,000	[1],[3],[4]	$ 37,504,000	[5],[7],[8]
TBA - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association (30 Year) 4 Point 00 Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2018-10	[1],[3],[4]	2018-01	[5],[7],[8]
Current Principal/Notional Amount		$ 66,903,000	[1],[3],[4]	$ 9,403,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 67,554,000	[1],[3],[4]	$ 9,835,000	[5],[7],[8]
TBA - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation (30 Year) 3 Point 50 Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2018-10	[1],[3],[4]	2018-01	[5],[7],[8]
Current Principal/Notional Amount		$ 21,540,000	[1],[3],[4]	$ 27,340,000	[5],[7],[8]
Rate		3.50%	[1],[3],[4]	3.50%	[5],[7],[8]
Investments Fair Value		$ 21,200,000	[1],[3],[4]	$ 28,085,000	[5],[7],[8]
TBA - Fixed Rate Agency Securities [Member] | Government National Mortgage Association (30 Year) 5 Point 50 Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[1],[3],[4]	2018-10
Current Principal/Notional Amount	[1],[3],[4]	$ 10,579,000
Rate	[1],[3],[4]	5.50%
Investments Fair Value	[1],[3],[4]	$ 11,159,000
TBA - Fixed Rate Agency Securities [Member] | Government National Mortgage Association (30 Year) 4 Point 00 Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2018-10	[1],[3],[4]	2018-01	[5],[7],[8]
Current Principal/Notional Amount		$ 3,740,000	[1],[3],[4]	$ 42,884,000	[5],[7],[8]
Rate		4.00%	[1],[3],[4]	4.00%	[5],[7],[8]
Investments Fair Value		$ 3,802,000	[1],[3],[4]	$ 44,738,000	[5],[7],[8]
TBA - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation (15 Year) 3 Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2018-10	[1],[3],[4]	2018-01	[5],[7],[8]
Current Principal/Notional Amount		$ 1,660,000	[1],[3],[4]	$ 470,000	[5],[7],[8]
Rate		3.00%	[1],[3],[4]	3.00%	[5],[7],[8]
Investments Fair Value		$ 1,636,000	[1],[3],[4]	$ 479,000	[5],[7],[8]
TBA - Fixed Rate Agency Securities [Member] | Government National Mortgage Association (30 Year) 3 Point 00 Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2018-01
Current Principal/Notional Amount	[5],[7],[8]			$ 2,100,000
Rate	[5],[7],[8]			3.00%
Investments Fair Value	[5],[7],[8]			$ 2,119,000
TBA - Fixed Rate Agency Securities [Member] | Government National Mortgage Association (30 Year) 3 Point 50 Percent [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[5],[7],[8]			2018-01
Current Principal/Notional Amount	[5],[7],[8]			$ 890,000
Rate	[5],[7],[8]			3.50%
Investments Fair Value	[5],[7],[8]			$ 920,000
Fixed Rate Agency Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		189.05%	[1],[2],[3],[4]	145.75%	[5],[6],[7],[8]
Investments Fair Value		$ 1,165,848,000	[1],[3],[4]	$ 905,025,000	[5],[7],[8]
Investment Owned, at Cost		$ 1,193,517,000	[1],[3],[4]	$ 911,909,000	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		9.88%	[1],[2],[3],[4]	11.10%	[5],[6],[7],[8]
Investments Fair Value		$ 60,935,000	[1],[3],[4]	$ 68,933,000	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member] | Government National Mortgage Association Pools [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		53,067,000	[1],[3],[4]	56,137,000	[5],[7],[8]
Investments Fair Value		$ 55,396,000	[1],[3],[4]	$ 60,866,000	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member] | Government National Mortgage Association Pools [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2061-07	[1],[3],[4]	2061-07	[5],[7],[8]
Rate		4.40%	[1],[3],[4]	3.59%	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member] | Government National Mortgage Association Pools [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2067-12	[1],[3],[4]	2067-10	[5],[7],[8]
Rate		4.67%	[1],[3],[4]	4.68%	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal National Mortgage Association Pools [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 3,555,000	[1],[3],[4]	$ 4,806,000	[5],[7],[8]
Investments Fair Value		$ 3,684,000	[1],[3],[4]	$ 4,999,000	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal National Mortgage Association Pools [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2035-09	[1],[3],[4]	2035-09	[5],[7],[8]
Rate		2.70%	[1],[3],[4]	2.79%	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal National Mortgage Association Pools [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2045-05	[1],[3],[4]	2045-05	[5],[7],[8]
Rate		4.69%	[1],[3],[4]	3.69%	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 1,822,000	[1],[3],[4]	$ 2,963,000	[5],[7],[8]
Investments Fair Value		$ 1,855,000	[1],[3],[4]	$ 3,068,000	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2037-06	[1],[3],[4]	2037-06	[5],[7],[8]
Rate		3.49%	[1],[3],[4]	3.49%	[5],[7],[8]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2044-05	[1],[3],[4]	2044-05	[5],[7],[8]
Rate		4.72%	[1],[3],[4]	4.80%	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		3.44%	[1],[2],[3],[4]	3.47%	[5],[6],[7],[8]
Investments Fair Value		$ 21,207,000	[1],[3],[4]	$ 21,556,000	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Government National Mortgage Association [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		263,738,000	[1],[3],[4]	313,840,000	[5],[7],[8]
Investments Fair Value		$ 12,099,000	[1],[3],[4]	$ 16,248,000	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Government National Mortgage Association [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2031-06	[1],[3],[4]	2037-03	[5],[7],[8]
Rate		0.40%	[1],[3],[4]	0.41%	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Government National Mortgage Association [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2066-10	[1],[3],[4]	2066-10	[5],[7],[8]
Rate		5.94%	[1],[3],[4]	5.31%	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Federal National Mortgage Association [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 80,590,000	[1],[3],[4]	$ 30,729,000	[5],[7],[8]
Investments Fair Value		$ 5,543,000	[1],[3],[4]	$ 3,506,000	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Federal National Mortgage Association [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2033-06	[1],[3],[4]	2033-06	[5],[7],[8]
Rate		1.12%	[1],[3],[4]	4.30%	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Federal National Mortgage Association [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2046-11	[1],[3],[4]	2041-12	[5],[7],[8]
Rate		5.50%	[1],[3],[4]	6.00%	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 52,492,000	[1],[3],[4]	$ 11,211,000	[5],[7],[8]
Investments Fair Value		$ 3,432,000	[1],[3],[4]	$ 1,436,000	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2036-03	[1],[3],[4]	2036-03	[5],[7],[8]
Rate		1.61%	[1],[3],[4]	4.52%	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2044-01	[1],[3],[4]	2040-04	[5],[7],[8]
Rate		4.49%	[1],[3],[4]	5.15%	[5],[7],[8]
Interest Only - Floating Rate Agency Securities [Member] | Resecuritization of Government National Mortgage Association [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2060-08	[1],[3],[4],[9]	2060-08	[5],[7],[8],[10]
Current Principal/Notional Amount		$ 6,544,000	[1],[3],[4],[9]	$ 10,619,000	[5],[7],[8],[10]
Rate		2.38%	[1],[3],[4],[9]	3.25%	[5],[7],[8],[10]
Investments Fair Value		$ 133,000	[1],[3],[4],[9]	$ 366,000	[5],[7],[8],[10]
Floating Rate Agency Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		13.32%	[1],[2],[3],[4]	14.57%	[5],[6],[7],[8]
Investments Fair Value		$ 82,142,000	[1],[3],[4]	$ 90,489,000	[5],[7],[8]
Investment Owned, at Cost		$ 85,774,000	[1],[3],[4]	$ 91,413,000	[5],[7],[8]
Agency Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		202.37%	[1],[2],[3],[4]	160.32%	[5],[6],[7],[8]
Investments Fair Value		$ 1,247,990,000	[1],[3],[4]	$ 995,514,000	[5],[7],[8]
Investment Owned, at Cost		$ 1,279,291,000	[1],[3],[4]	$ 1,003,322,000	[5],[7],[8]
Principal And Interest - Private Label Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		63.57%	[2],[3],[4]	47.12%	[6],[7],[8]
Investments Fair Value		$ 392,047,000	[3],[4]	$ 292,566,000	[7],[8]
Investment Owned, at Cost		$ 382,266,000	[3],[4]	$ 278,803,000	[7],[8]
Principal And Interest - Private Label Securities [Member] | North America [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		30.44%	[2],[3],[4]	29.16%	[6],[7],[8]
Investments Fair Value		$ 187,754,000	[3],[4]	$ 181,042,000	[7],[8]
Investment Owned, at Cost		$ 176,842,000	[3],[4]	$ 172,285,000	[7],[8]
Principal And Interest - Private Label Securities [Member] | Europe [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		33.13%	[2],[3],[4]	17.96%	[6],[7],[8]
Investments Fair Value		$ 204,293,000	[3],[4]	$ 111,524,000	[7],[8]
Investment Owned, at Cost		205,424,000	[3],[4]	106,518,000	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		33,819,000	[3],[4]	80,114,000	[7],[8]
Investments Fair Value		11,641,000	[3],[4]	26,155,000	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		245,943,000	[3],[4]	232,771,000	[7],[8]
Investments Fair Value		176,113,000	[3],[4]	154,887,000	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Europe [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		25,841,000	[3],[4]	23,752,000	[7],[8]
Investments Fair Value		16,250,000	[3],[4]	11,601,000	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Europe [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		221,257,000	[3],[4]	127,469,000	[7],[8]
Investments Fair Value		$ 188,043,000	[3],[4]	$ 99,923,000	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2049-03	[3],[4]	2035-08	[7],[8]
Rate		2.80%	[3],[4]	2.05%	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2019-05	[3],[4]	2019-05	[7],[8]
Rate		0.00%	[3],[4]	0.00%	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | Europe [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2020-10	[3],[4]	2020-10	[7],[8]
Rate		0.38%	[3],[4]	0.37%	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | Europe [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2025-06	[3],[4]	2025-06	[7],[8]
Rate		0.00%	[3],[4]	0.00%	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2061-05	[3],[4]	2058-09	[7],[8]
Rate		3.44%	[3],[4]	4.41%	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2047-03	[3],[4]	2046-09	[7],[8]
Rate		26.31%	[3],[4]	30.29%	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | Europe [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2045-08	[3],[4]	2041-02	[7],[8]
Rate		4.20%	[3],[4]	5.03%	[7],[8]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | Europe [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2061-12	[3],[4]	2061-01	[7],[8]
Rate		5.50%	[3],[4]	5.50%	[7],[8]
Interest Only - Private Label Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		1.20%	[2],[3],[4]	1.26%	[6],[7],[8]
Investments Fair Value		$ 7,392,000	[3],[4]	$ 7,845,000	[7],[8]
Investment Owned, at Cost		5,361,000	[3],[4]	5,334,000	[7],[8]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		41,707,000	[3],[4]	39,871,000	[7],[8]
Investments Fair Value		3,282,000	[3],[4]	2,989,000	[7],[8]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		32,210,000	[3],[4]	36,008,000	[7],[8]
Investments Fair Value		$ 4,110,000	[3],[4]	$ 4,856,000	[7],[8]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2049-03	[3],[4]	2049-03	[7],[8]
Rate		1.25%	[3],[4]	1.25%	[7],[8]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2030-12	[3],[4]	2030-12	[7],[8]
Rate		0.00%	[3],[4]	0.00%	[7],[8]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2061-05	[3],[4]	2049-12	[7],[8]
Rate		2.00%	[3],[4]	2.00%	[7],[8]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2047-09	[3],[4]	2047-09	[7],[8]
Rate		2.00%	[3],[4]	2.00%	[7],[8]
Other Private Label Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		0.00%	[2],[3],[4]	0.00%	[6],[7],[8]
Investments Fair Value		$ 0	[3],[4]	$ 0	[7],[8]
Investment Owned, at Cost		191,000	[3],[4]	215,000	[7],[8]
Other Private Label Securities [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		$ 0	[3],[4]	$ 0	[7],[8]
Rate		0.00%	[3],[4]	0.00%	[7],[8]
Investments Fair Value		$ 0	[3],[4]	$ 0	[7],[8]
Other Private Label Securities [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2037-06	[3],[4]	2037-06	[7],[8]
Current Principal/Notional Amount		$ 70,577,000	[3],[4]	$ 79,487,000	[7],[8]
Rate		0.00%	[3],[4]	0.00%	[7],[8]
Investments Fair Value		$ 0	[3],[4]	$ 0	[7],[8]
Other Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2045-07	[3],[4]	2045-07	[7],[8]
Other Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2061-05	[3],[4]	2049-12	[7],[8]
Private Label Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		64.77%	[2],[3],[4]	48.38%	[6],[7],[8]
Investments Fair Value		$ 399,439,000	[3],[4]	$ 300,411,000	[7],[8]
Investment Owned, at Cost		$ 387,818,000	[3],[4]	$ 284,352,000	[7],[8]
Mortgage-Backed Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		267.14%	[2],[3],[4]	208.70%	[6],[7],[8]
Investments Fair Value		$ 1,647,429,000	[3],[4]	$ 1,295,925,000	[7],[8]
Investment Owned, at Cost		$ 1,667,109,000	[3],[4]	$ 1,287,674,000	[7],[8]
Collateralized Loan Obligations [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		25.31%	[2],[3],[4]	33.95%	[6],[7],[8]
Investments Fair Value		$ 156,087,000	[3],[4]	$ 210,816,000	[7],[8]
Investment Owned, at Cost		$ 160,561,000	[3],[4]	$ 212,998,000	[7],[8]
Collateralized Loan Obligations [Member] | North America [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		23.79%	[2],[3],[4],[11]	27.40%	[6],[7],[8],[12]
Investments Fair Value		$ 146,713,000	[3],[4],[11]	$ 170,123,000	[7],[8],[12]
Investment Owned, at Cost		$ 151,155,000	[3],[4],[11]	$ 174,635,000	[7],[8],[12]
Collateralized Loan Obligations [Member] | Europe [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		1.52%	[2],[3],[4]	6.55%	[6],[7],[8]
Investments Fair Value		$ 9,374,000	[3],[4]	$ 40,693,000	[7],[8]
Investment Owned, at Cost		9,406,000	[3],[4]	38,363,000	[7],[8]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | North America [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		286,284,000	[3],[4],[11]	278,601,000	[7],[8],[12]
Investments Fair Value		$ 146,713,000	[3],[4],[11]	170,123,000	[7],[8],[12]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Europe [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4]	2024-04
Current Principal/Notional Amount		$ 9,993,000	[3],[4]	42,101,000	[7],[8]
Rate	[3],[4]	7.95%
Investments Fair Value		$ 9,374,000	[3],[4]	$ 40,693,000	[7],[8]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member]
Schedule of Investments [Line Items]
Investments maturity date		2018-12	[3],[4],[11]	2018-01	[7],[8],[12]
Rate		0.00%	[3],[4],[11]	0.00%	[7],[8],[12]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Minimum [Member] | Europe [Member]
Schedule of Investments [Line Items]
Investments maturity date	[7],[8]			2022-04
Rate	[7],[8]			0.00%
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member]
Schedule of Investments [Line Items]
Investments maturity date		2118-10	[3],[4],[11]	2057-11	[7],[8],[12]
Rate		10.09%	[3],[4],[11]	10.04%	[7],[8],[12]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Maximum [Member] | Europe [Member]
Schedule of Investments [Line Items]
Investments maturity date	[7],[8]			2027-01
Rate	[7],[8]			7.95%
Consumer loans and asset-backed securities backed by consumer loans [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		33.16%	[2],[3],[4],[13]	21.78%	[6],[7],[8],[14]
Investments Fair Value		$ 204,504,000	[3],[4],[13]	$ 135,258,000	[7],[8],[14]
Investment Owned, at Cost		$ 208,662,000	[3],[4],[13]	$ 139,387,000	[7],[8],[14]
Consumer loans and asset-backed securities backed by consumer loans [Member] | North America [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		33.01%	[2],[3],[4],[13]	21.34%	[6],[7],[8],[14]
Investments Fair Value		$ 203,585,000	[3],[4],[13]	$ 132,509,000	[7],[8],[14]
Investment Owned, at Cost		$ 207,837,000	[3],[4],[13]	$ 138,312,000	[7],[8],[14]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Europe [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		0.15%	[2],[3],[4],[13]	0.44%	[6],[7],[8],[14]
Investments Fair Value		$ 919,000	[3],[4],[13]	$ 2,749,000	[7],[8],[14]
Investment Owned, at Cost		825,000	[3],[4],[13]	1,075,000	[7],[8],[14]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | North America [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		224,476,000	[3],[4],[13],[15],[16]	151,753,000	[7],[8],[14],[17],[18]
Investments Fair Value		$ 203,585,000	[3],[4],[13],[15],[16]	132,509,000	[7],[8],[14],[17],[18]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | Europe [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4],[13]	2030-12
Current Principal/Notional Amount		$ 3,588,000	[3],[4],[13]	$ 3,711,000	[7],[8],[14]
Rate		0.00%	[3],[4],[13]	0.00%	[7],[8],[14]
Investments Fair Value		$ 919,000	[3],[4],[13]	$ 2,749,000	[7],[8],[14]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments maturity date		2018-10	[3],[4],[13],[15],[16]	2018-01	[7],[8],[14],[17],[18]
Rate		5.31%	[3],[4],[13],[15],[16]	5.31%	[7],[8],[14],[17],[18]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | Minimum [Member] | Europe [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments maturity date	[7],[8],[14]			2024-08
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments maturity date		2023-09	[3],[4],[13],[15],[16]	2022-09	[7],[8],[14],[17],[18]
Rate		76.50%	[3],[4],[13],[15],[16]	76.28%	[7],[8],[14],[17],[18]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | Maximum [Member] | Europe [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments maturity date	[7],[8],[14]			2030-12
Corporate Debt [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		8.71%	[2],[3],[4]	12.11%	[6],[7],[8]
Investments Fair Value		$ 53,718,000	[3],[4]	$ 75,193,000	[7],[8]
Investment Owned, at Cost		$ 52,157,000	[3],[4]	$ 75,952,000	[7],[8]
Corporate Debt [Member] | North America [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		6.86%	[2],[3],[4]	9.76%	[6],[7],[8]
Investments Fair Value		$ 42,293,000	[3],[4]	$ 60,618,000	[7],[8]
Investment Owned, at Cost		$ 39,487,000	[3],[4]	$ 60,640,000	[7],[8]
Corporate Debt [Member] | Europe [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		1.85%	[2],[3],[4]	2.35%	[6],[7],[8]
Investments Fair Value		$ 11,425,000	[3],[4]	$ 14,575,000	[7],[8]
Investment Owned, at Cost		12,670,000	[3],[4]	15,312,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | North America [Member] | Basic Materials [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		3,224,000	[3],[4]	6,025,000	[7],[8]
Investments Fair Value		3,201,000	[3],[4]	6,254,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | North America [Member] | Communications [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		4,241,000	[3],[4]	8,490,000	[7],[8]
Investments Fair Value		4,522,000	[3],[4]	8,523,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | North America [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		13,331,000	[3],[4]	21,993,000	[7],[8]
Investments Fair Value		$ 13,345,000	[3],[4]	23,043,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | North America [Member] | Energy [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4]	2021-09
Current Principal/Notional Amount		$ 2,080,000	[3],[4]	9,665,000	[7],[8]
Rate	[3],[4]	4.63%
Investments Fair Value		$ 2,063,000	[3],[4]	$ 10,266,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | North America [Member] | Financial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2022-08	[3],[4]	2024-09	[7],[8]
Current Principal/Notional Amount		$ 355,000	[3],[4]	$ 560,000	[7],[8]
Rate		5.00%	[3],[4]	5.13%	[7],[8]
Investments Fair Value		$ 363,000	[3],[4]	$ 606,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | North America [Member] | Industrial Sector [Member]
Schedule of Investments [Line Items]
Investments maturity date	[7],[8]			2021-12
Current Principal/Notional Amount		11,995,000	[3],[4]	$ 2,250,000	[7],[8]
Rate	[7],[8]			3.75%
Investments Fair Value		11,789,000	[3],[4]	$ 2,286,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[7],[8],[19]			2019-10
Current Principal/Notional Amount	[7],[8],[19]			$ 5,429,000
Rate	[7],[8],[19]			15.00%
Investments Fair Value	[7],[8],[19]			$ 5,429,000
Corporate Debt [Member] | Various Issuer [Member] | North America [Member] | Technology Sector [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		7,612,000	[3],[4]	4,300,000	[7],[8]
Investments Fair Value		$ 7,010,000	[3],[4]	$ 4,211,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Europe [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments maturity date		2018-12	[3],[4]	2018-03	[7],[8]
Current Principal/Notional Amount		$ 20,807,000	[3],[4]	$ 20,070,000	[7],[8]
Rate		0.00%	[3],[4]	0.00%	[7],[8]
Investments Fair Value		$ 52,000	[3],[4]	$ 50,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Europe [Member] | Financial [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		11,782,000	[3],[4]	13,725,000	[7],[8]
Investments Fair Value		$ 11,373,000	[3],[4]	$ 13,437,000	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Europe [Member] | Industrial Sector [Member]
Schedule of Investments [Line Items]
Investments maturity date	[7],[8]			2021-03
Current Principal/Notional Amount	[7],[8]			$ 1,145,000
Rate	[7],[8]			1.59%
Investments Fair Value	[7],[8]			$ 1,088,000
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Basic Materials [Member]
Schedule of Investments [Line Items]
Investments maturity date		2021-10	[3],[4]	2025-08	[7],[8]
Rate		3.55%	[3],[4]	6.88%	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Communications [Member]
Schedule of Investments [Line Items]
Investments maturity date		2020-04	[3],[4]	2020-04	[7],[8]
Rate		0.00%	[3],[4]	3.40%	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments maturity date		2020-03	[3],[4]	2019-01	[7],[8]
Rate		3.55%	[3],[4]	2.60%	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Energy [Member]
Schedule of Investments [Line Items]
Investments maturity date	[7],[8]			2019-03
Rate	[7],[8]			4.50%
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Industrial Sector [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4]	2021-04
Rate	[3],[4]	3.25%
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Technology Sector [Member]
Schedule of Investments [Line Items]
Investments maturity date		2020-05	[3],[4]	2021-10	[7],[8]
Rate		3.88%	[3],[4]	3.63%	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | Europe [Member] | Financial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2020-10	[3],[4]	2020-10	[7],[8]
Rate		0.00%	[3],[4]	0.00%	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Basic Materials [Member]
Schedule of Investments [Line Items]
Investments maturity date		2022-03	[3],[4]	2027-03	[7],[8]
Rate		7.63%	[3],[4]	7.00%	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Communications [Member]
Schedule of Investments [Line Items]
Investments maturity date		2022-05	[3],[4]	2027-08	[7],[8]
Rate		11.50%	[3],[4]	11.57%	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments maturity date		2028-03	[3],[4]	2034-12	[7],[8]
Rate		12.81%	[3],[4]	9.73%	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Energy [Member]
Schedule of Investments [Line Items]
Investments maturity date	[7],[8]			2025-08
Rate	[7],[8]			9.63%
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Industrial Sector [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4]	2028-01
Rate	[3],[4]	5.40%
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Technology Sector [Member]
Schedule of Investments [Line Items]
Investments maturity date		2022-05	[3],[4]	2022-08	[7],[8]
Rate		7.32%	[3],[4]	7.50%	[7],[8]
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | Europe [Member] | Financial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2022-11	[3],[4]	2022-11	[7],[8]
Rate		16.00%	[3],[4]	15.67%	[7],[8]
Secured Notes [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity	[2],[3],[4],[20]	1.80%
Investments Fair Value	[3],[4],[20]	$ 11,065,000
Investment Owned, at Cost	[3],[4],[20]	$ 11,766,000
Secured Notes [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4],[20]	2057-11
Current Principal/Notional Amount	[3],[4],[20]	$ 17,847,000
Rate	[3],[4],[20]	5.00%
Investments Fair Value	[3],[4],[20]	$ 11,065,000
Mortgage Loans [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		84.04%	[2],[3],[4],[13]	46.83%	[6],[7],[8],[14]
Investments Fair Value		$ 518,268,000	[3],[4],[13]	$ 290,773,000	[7],[8],[14]
Investment Owned, at Cost		515,877,000	[3],[4],[13]	288,034,000	[7],[8],[14]
Mortgage Loans [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		126,334,000	[3],[4],[13],[21]	116,707,000	[7],[8],[14],[22]
Investments Fair Value		125,808,000	[3],[4],[13],[21]	108,301,000	[7],[8],[14],[22]
Mortgage Loans [Member] | Various Issuer [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Current Principal/Notional Amount		391,816,000	[3],[4],[13],[23],[24]	181,553,000	[7],[8],[14],[25],[26]
Investments Fair Value		$ 392,460,000	[3],[4],[13],[23],[24]	$ 182,472,000	[7],[8],[14],[25],[26]
Mortgage Loans [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2018-10	[3],[4],[13],[21]	2018-02	[7],[8],[14],[22]
Rate		3.73%	[3],[4],[13],[21]	3.14%	[7],[8],[14],[22]
Mortgage Loans [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2019-02	[3],[4],[13],[23],[24]	2022-04	[7],[8],[14],[25],[26]
Rate		2.00%	[3],[4],[13],[23],[24]	2.00%	[7],[8],[14],[25],[26]
Mortgage Loans [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments maturity date		2037-10	[3],[4],[13],[21]	2037-10	[7],[8],[14],[22]
Rate		13.61%	[3],[4],[13],[21]	12.87%	[7],[8],[14],[22]
Mortgage Loans [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments maturity date		2058-09	[3],[4],[13],[23],[24]	2057-04	[7],[8],[14],[25],[26]
Rate		15.00%	[3],[4],[13],[23],[24]	12.63%	[7],[8],[14],[25],[26]
Real Estate Owned [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		5.67%	[2],[3],[4],[13],[27]	4.23%	[6],[7],[8],[14],[28]
Investments Fair Value		$ 34,944,000	[3],[4],[13],[27]	$ 26,277,000	[7],[8],[14],[28]
Investment Owned, at Cost		33,867,000	[3],[4],[13],[27]	26,146,000	[7],[8],[14],[28]
Real Estate Owned [Member] | Single-Family Houses [Member] | North America [Member] | Real estate-related [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 1,386,000	[3],[4],[13],[27]	$ 591,000	[7],[8],[14],[28]
Number of Real Estate Properties		5	[3],[4],[13],[27]	3	[7],[8],[14],[28]
Real Estate Owned [Member] | Commercial Property [Member] | North America [Member] | Real estate-related [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 33,558,000	[3],[4],[13],[27]	$ 25,686,000	[7],[8],[14],[28]
Number of Real Estate Properties		18	[3],[4],[13],[27]	9	[7],[8],[14],[28]
Corporate Equity Investments [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		6.46%	[2],[3],[4]	6.03%	[6],[7],[8]
Investments Fair Value		$ 39,824,000	[3],[4]	$ 37,465,000	[7],[8]
Investment Owned, at Cost		39,967,000	[3],[4]	$ 41,563,000	[7],[8]
Corporate Equity Investments [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 1,100,000
Corporate Equity Investments [Member] | North America [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		6.46%	[2],[3],[4]	6.03%	[6],[7],[8]
Investments Fair Value		$ 39,820,000	[3],[4]	$ 37,461,000	[7],[8]
Investment Owned, at Cost		$ 39,963,000	[3],[4]	$ 41,559,000	[7],[8]
Corporate Equity Investments [Member] | Europe [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		0.00%	[2],[3],[4]	0.00%	[6],[7],[8]
Investments Fair Value		$ 4,000	[3],[4]	$ 4,000	[7],[8]
Investment Owned, at Cost		4,000	[3],[4]	4,000	[7],[8]
Corporate Equity Investments [Member] | Non-Controlling Equity Interest in Limited Liability Company [Member] | North America [Member] | Asset-backed Securities [Member]
Schedule of Investments [Line Items]
Investments Fair Value	[7],[8],[29]			5,033,000
Corporate Equity Investments [Member] | Non-Controlling Equity Interest in Limited Liability Company [Member] | North America [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments Fair Value		6,263,000	[3],[4],[30]	5,693,000	[7],[8],[29]
Corporate Equity Investments [Member] | Non-Exchange Traded Corporate Equity [Member] | North America [Member] | Communications [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 111,000	[3],[4]	$ 557,000	[7],[8]
Investment Owned, Balance, Shares		7	[3],[4]	7	[7],[8]
Corporate Equity Investments [Member] | Non-Exchange Traded Corporate Equity [Member] | North America [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 2,000	[3],[4]	$ 5,000	[7],[8]
Investment Owned, Balance, Shares		1,540	[3],[4]	1,540	[7],[8]
Corporate Equity Investments [Member] | Non-Exchange Traded Corporate Equity [Member] | North America [Member] | Diversified [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 1,455,000	[3],[4]	$ 2,585,000	[7],[8]
Investment Owned, Balance, Shares		144	[3],[4]	156	[7],[8]
Corporate Equity Investments [Member] | Non-Exchange Traded Corporate Equity [Member] | Europe [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 0	[3],[4]	$ 0	[7],[8]
Investment Owned, Balance, Shares		125	[3],[4]	125	[7],[8]
Corporate Equity Investments [Member] | Non-Exchange Traded Corporate Equity [Member] | Europe [Member] | Financial [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 4,000	[3],[4]	$ 4,000	[7],[8]
Investment Owned, Balance, Shares		0	[3],[4]	0	[7],[8]
Corporate Equity Investments [Member] | Exchange Traded Equity [Member] | North America [Member] | Consumer [Member]
Schedule of Investments [Line Items]
Investments Fair Value	[3],[4]	$ 60,000
Investment Owned, Balance, Shares	[3],[4]	36
Corporate Equity Investments [Member] | Exchange Traded Equity [Member] | North America [Member] | Financial [Member]
Schedule of Investments [Line Items]
Investments Fair Value	[3],[4]	$ 609,000
Investment Owned, Balance, Shares	[3],[4]	49
Corporate Equity Investments [Member] | Non-controlling Interest in Mortgage-related Private Partnership [Member] | North America [Member] | Mortgage-related Commercial [Member]
Schedule of Investments [Line Items]
Investments Fair Value	[3],[4],[20]	$ 1,149,000
Corporate Equity Investments [Member] | Non-Exchange Traded Preferred Equity Investment in Mortgage Originators [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 27,357,000	[3],[4],[20]	$ 20,774,000	[7],[8],[19]
Investment Owned, Balance, Shares		23	[3],[4],[20]	20	[7],[8],[19]
Corporate Equity Investments [Member] | Non-Exchange Traded Equity Investment in Mortgage Originators [Member] | North America [Member] | Mortgage-related Residential [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 2,814,000	[3],[4],[20]	$ 2,814,000	[7],[8],[19]
Investment Owned, Balance, Shares		9,818	[3],[4],[20]	9,818	[7],[8],[19]
US Treasury Securities [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity	[2],[3],[4]	0.69%
Investments Fair Value	[3],[4]	$ 4,230,000
Investment Owned, at Cost	[3],[4]	$ 4,257,000
US Treasury Securities [Member] | U.S. Treasury Note, 2.25 Percent, Maturity Date 2027 11 [Member] | North America [Member] | Government [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4]	2027-11
Current Principal/Notional Amount	[3],[4]	$ 1,995,000
Rate	[3],[4]	2.25%
Investments Fair Value	[3],[4]	$ 1,868,000
US Treasury Securities [Member] | U.S. Treasury Note, 2.75 Percent, Maturity Date 2023 07 [Member] | North America [Member] | Government [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4]	2023-07
Current Principal/Notional Amount	[3],[4]	$ 882,000
Rate	[3],[4]	2.75%
Investments Fair Value	[3],[4]	$ 874,000
US Treasury Securities [Member] | U.S. Treasury Note, 2.75 Percent, Maturity Date 2028 02 [Member] | North America [Member] | Government [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4]	2028-02
Current Principal/Notional Amount	[3],[4]	$ 806,000
Rate	[3],[4]	2.75%
Investments Fair Value	[3],[4]	$ 786,000
US Treasury Securities [Member] | U.S. Treasury Note, 2.63 Percent, Maturity Date 2020 08 [Member] | North America [Member] | Government [Member]
Schedule of Investments [Line Items]
Investments maturity date	[3],[4]	2020-08
Current Principal/Notional Amount	[3],[4]	$ 704,000
Rate	[3],[4]	2.63%
Investments Fair Value	[3],[4]	$ 702,000
Long Investments [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		432.98%	[2],[3],[4]	333.63%	[6],[7],[8]
Investments Fair Value		$ 2,670,069,000	[3],[4]	$ 2,071,707,000	[7],[8]
Investment Owned, at Cost		$ 2,694,223,000	[3],[4]	$ 2,071,754,000	[7],[8]
Long Investments [Member] | Government National Mortgage Association [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		77.76%		45.07%
Long Investments [Member] | Federal National Mortgage Association [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		82.74%		72.39%
Long Investments [Member] | Federal Home Loan Mortgage Corporation [Member]
Schedule of Investments [Line Items]
Investment owned as a percentage of equity		41.87%		42.86%
Securitized Residential Mortgage Loans [Member]
Schedule of Investments [Line Items]
Fair value of Assets Transfered and Accounted for as Secured Borrowings		$ 95,000,000		$ 132,400,000
Related Party CLO securitization [Member] | Collateralized Loan Obligations [Member]
Schedule of Investments [Line Items]
Investments Fair Value		$ 61,600,000		$ 37,700,000

[1] At September 30, 2018, the Company's long investments guaranteed by the Federal National Mortgage Association, the Federal Home Loan Mortgage Corporation, and the Government National Mortgage Association, represented 82.74%, 41.87%, and 77.76% of Total Equity, respectively.

[2] Classification percentages are based on Total Equity.

[3] See Note 2 and Note 3 in Notes to Consolidated Financial Statements.

[4] The table below shows the Company's long investment ratings from Moody's, Standard and Poor's, or Fitch, as well as the Company's long investments that were unrated but guaranteed by the Federal National Mortgage Association, the Federal Home Loan Mortgage Corporation, or the Government National Mortgage Association. Ratings tend to be a lagging credit indicator; as a result, the credit quality of the Company's long investment holdings may be lower than the credit quality implied based on the ratings listed below. In situations where an investment has a split rating, the lowest provided rating is used. The ratings descriptions include ratings qualified with a "+," "-," "1," "2," or "3."Rating Description Percent of EquityUnrated but Agency-Guaranteed 202.37%Aaa/AAA/AAA 0.69%Aa/AA/AA 0.90%A/A/A 5.98%Baa/BBB/BBB 6.06%Ba/BB/BB or below 61.53%Unrated 155.45%

[5] At December 31, 2017, the Company's long investments guaranteed by the Federal National Mortgage Association, the Federal Home Loan Mortgage Corporation, and the Government National Mortgage Association, represented 72.39%, 42.86%, and 45.07% of Total Equity, respectively.

[6] Classification percentages are based on Total Equity.

[7] See Note 2 and Note 3 in Notes to Consolidated Financial Statements.

[8] The table below shows the ratings on the Company's long investments from Moody's, Standard and Poor's, or Fitch, as well as the Company's long investments that were unrated but guaranteed by the Federal National Mortgage Association, the Federal Home Loan Mortgage Corporation, or the Government National Mortgage Association. Ratings tend to be a lagging credit indicator; as a result, the credit quality of the Company's long investment holdings may be lower than the credit quality implied based on the ratings listed below. In situations where an investment has a split rating, the lowest provided rating is used. The ratings descriptions include ratings qualified with a "+," "-," "1," "2," or "3."Rating Description Percent of EquityUnrated but Agency-Guaranteed 160.32%A/A/A 0.81%Baa/BBB/BBB 2.62%Ba/BB/BB or below 68.03%Unrated 101.85%

[9] Private trust 100% backed by interest in Government National Mortgage Association collateralized mortgage obligation certificates.

[10] Private trust 100% backed by interest in Government National Mortgage Association collateralized mortgage obligation certificates.

[11] Includes investment in collateralized loan obligation notes in the amount of $61.6 million that were issued and are managed by related parties of the Company. See Note 9 to the Notes to Consolidated Financial Statements.

[12] Includes investment in collateralized loan obligation notes in the amount of $37.7 million that were issued and are managed by related parties of the Company. See Note 9 to the Notes to Consolidated Financial Statements.

[13] Loans and real estate owned are beneficially owned by the Company through participation certificates in the various trusts that hold such investments. See Note 9 to the Notes to Consolidated Financial Statements.

[14] Loans and real estate owned are beneficially owned by the Company through participation certificates in the various trusts that hold such investments. See Note 9 to the Notes to Consolidated Financial Statements.

[15] Includes investments in participation certificates related to loans held in a trust owned by a related party of Ellington Management Group, L.L.C. Through its participation certificates, the Company participates in the cash flows of the underlying loans held by the trust. At September 30, 2018 loans held in the related party trust for which the Company has participating interests in the cash flows, totaled $180.7 million. See Note 9 to the Notes to Consolidated Financial Statements.

[16] Includes investments in participation certificates related to loans titled in the name of a related party of Ellington Management Group, L.L.C. Through its participation certificates, the Company has beneficial interests in the loan cash flows, net of servicing-related fees and expenses. At September 30, 2018 loans for which the Company has beneficial interests in the net cash flows, totaled $19.8 million. See Note 9 to the Notes to Consolidated Financial Statements.

[17] Includes investments in participation certificates related to loans held in a trust owned by a related party of Ellington Management Group, L.L.C. Through its participation certificates, the Company participates in the cash flows of the underlying loans held by the trust. At December 31, 2017 loans held in the related party trust for which the Company has participating interests in the cash flows, totaled $114.5 million. See Note 9 to the Notes to Consolidated Financial Statements.

[18] Includes investments in participation certificates related to loans titled in the name of a related party of Ellington Financial Management, LLC. Through its participation certificates, the Company has beneficial interests in the loan cash flows, net of servicing-related fees and expenses. At December 31, 2017 loans for which the Company has beneficial interests in the net cash flows, totaled $11.7 million. See Note 9 to the Notes to Consolidated Financial Statements.

[19] Represents the Company's investment in a related party. See Note 9 to the Notes to Consolidated Financial Statements.

[20] Represents the Company's investment in a related party. See Note 9 to the Notes to Consolidated Financial Statements

[21] Includes non-performing commercial mortgage loans in the amount of $3.5 million whereby principal and/or interest is past due and a maturity date is not applicable.

[22] Includes non-performing commercial mortgage loans in the amount of $23.9 million whereby principal and/or interest is past due and a maturity date is not applicable.

[23] As of September 30, 2018, the Company had residential mortgage loans that were in the process of foreclosure with a fair value of $9.3 million.

[24] Includes $95.0 million of non-qualified mortgage loans that have been securitized and are held in a consolidated securitization trust. See Note 6 to the Notes to Consolidated Financial Statements.

[25] As of December 31, 2017, the Company had residential mortgage loans that were in the process of foreclosure with a fair value of $5.2 million.

[26] Includes $132.4 million of non-qualified mortgage loans that have been securitized and are held in a consolidated securitization trust. See Note 6 to the Notes to Consolidated Financial Statements.

[27] Number of properties not shown in thousands, represents actual number of properties owned.

[28] Number of properties not shown in thousands, represents actual number of properties owned.

[29] Represents the Company's beneficial interest in an entity, which is co-owned by an affiliate of Ellington Management Group, L.L.C. The entity owns subordinated notes issued by, as well as trust certificates representing ownership of, a securitization trust. See Note 6 and Note 9 to the Notes to Consolidated Financial Statements.

[30] Represents the Company's beneficial interest in an entity, which is co-owned by an affiliate of Ellington Management Group, L.L.C. The entity owns subordinated notes issued by, as well as trust certificates representing ownership of, a securitization trust. See Note 6 and Note 9 to the Notes to Consolidated Financial Statements.