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Consolidated Condensed Schedule Of Investments (Long Investments) - USD ($)
shares in Thousands
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Schedule of Investments [Line Items]    
Fair Value $ 1,661,118,000 $ 2,172,082,000
Investment Owned, at Cost $ 1,672,400,000 $ 2,122,326,000
Percentage collaterallized by GNRCMO certificates 100.00% 100.00%
Fair value of loans held in related party trust $ 3,800,000  
Non-performing loans, maturity date not applicable 22,600,000 $ 11,300,000
Mortgage Loans in Process of Foreclosure, Amount $ 5,900,000  
Unrated But Agency-Guaranteed [Member]    
Schedule of Investments [Line Items]    
Long investment holdings as a percentage of stockholders' equity 143.52% 163.60%
Long Investment A Rating [Member]    
Schedule of Investments [Line Items]    
Long investment holdings as a percentage of stockholders' equity 0.32% 0.98%
Long Investment BBB Rating [Member]    
Schedule of Investments [Line Items]    
Long investment holdings as a percentage of stockholders' equity 1.07% 5.62%
Long Investment BB Rating [Member]    
Schedule of Investments [Line Items]    
Long investment holdings as a percentage of stockholders' equity 34.89% 80.65%
Long Investment Unrated Rating [Member]    
Schedule of Investments [Line Items]    
Long investment holdings as a percentage of stockholders' equity 44.99% 24.61%
Principal And Interest - Fixed Rate Agency Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 124.31% [1],[2],[3],[4] 147.82% [5],[6],[7],[8],[9]
Fair Value $ 918,562,000 [1],[3],[4] $ 1,165,642,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 160,391,000 [1],[3],[4] $ 176,029,000 [5],[7],[8],[9]
Rate 4.00% [1],[3],[4] 4.00% [5],[7],[8],[9]
Fair Value $ 170,500,000 [1],[3],[4] $ 188,912,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 4.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2042-09 [1],[3],[4] 2042-09 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 4.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2045-08 [1],[3],[4] 2045-01 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 128,637,000 [1],[3],[4] $ 191,734,000 [5],[7],[8],[9]
Rate 4.00% [1],[3],[4] 4.00% [5],[7],[8],[9]
Fair Value $ 136,894,000 [1],[3],[4] $ 206,080,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 4.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2042-08 [1],[3],[4] 2042-04 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 4.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2045-10 [1],[3],[4] 2045-01 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 110,746,000 [1],[3],[4] $ 171,291,000 [5],[7],[8],[9]
Rate 4.50% [1],[3],[4] 4.50% [5],[7],[8],[9]
Fair Value $ 120,785,000 [1],[3],[4] $ 187,748,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 4.50% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2041-10 [1],[3],[4] 2041-10 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 4.50% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2045-10 [1],[3],[4] 2045-01 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 3.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 72,425,000 [1],[3],[4] $ 63,040,000 [5],[7],[8],[9]
Rate 3.50% [1],[3],[4] 3.50% [5],[7],[8],[9]
Fair Value $ 74,959,000 [1],[3],[4] $ 65,989,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 3.50% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2042-10 [1],[3],[4] 2042-10 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 3.50% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2045-10 [1],[3],[4] 2044-11 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 5.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 54,658,000 [1],[3],[4] $ 93,720,000 [5],[7],[8],[9]
Rate 5.00% [1],[3],[4] 5.00% [5],[7],[8],[9]
Fair Value $ 60,473,000 [1],[3],[4] $ 104,347,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 5.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2035-10 [1],[3],[4] 2035-10 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 5.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2044-12 [1],[3],[4] 2044-12 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 45,792,000 [1],[3],[4] $ 84,478,000 [5],[7],[8],[9]
Rate 3.50% [1],[3],[4] 3.50% [5],[7],[8],[9]
Fair Value $ 48,211,000 [1],[3],[4] $ 89,707,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.50% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2028-03 [1],[3],[4] 2028-03 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.50% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2030-10 [1],[3],[4] 2029-12 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 42,655,000 [1],[3],[4] $ 71,332,000 [5],[7],[8],[9]
Rate 4.50% [1],[3],[4] 4.50% [5],[7],[8],[9]
Fair Value $ 46,365,000 [1],[3],[4] $ 78,285,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 4.50% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2043-09 [1],[3],[4] 2043-09 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 4.50% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2045-10 [1],[3],[4] 2044-12 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 31,481,000  
Rate [1],[3],[4] 4.00%  
Fair Value [1],[3],[4] $ 33,620,000  
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [1],[3],[4] 2045-06  
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [1],[3],[4] 2045-10  
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 3.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 29,417,000 [1],[3],[4] $ 53,456,000 [5],[7],[8],[9]
Rate 3.50% [1],[3],[4] 3.50% [5],[7],[8],[9]
Fair Value $ 30,458,000 [1],[3],[4] $ 55,840,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 3.50% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2042-01 [1],[3],[4] 2042-01 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 3.50% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2045-10 [1],[3],[4] 2045-01 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 3.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 21,705,000 [1],[3],[4] $ 21,139,000 [5],[7],[8],[9]
Rate 3.50% [1],[3],[4] 3.50% [5],[7],[8],[9]
Fair Value $ 22,848,000 [1],[3],[4] $ 22,410,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 3.50% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2028-09 [1],[3],[4] 2028-09 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 3.50% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2030-09 [1],[3],[4] 2029-09 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 15,056,000  
Rate [1],[3],[4] 4.50%  
Fair Value [1],[3],[4] $ 16,328,000  
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.50% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [1],[3],[4] 2045-08  
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 4.50% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [1],[3],[4] 2045-09  
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 13,060,000  
Rate [1],[3],[4] 3.00%  
Fair Value [1],[3],[4] $ 13,500,000  
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 3.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [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] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [1],[3],[4] 2030-10  
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 11,558,000 [1],[3],[4] $ 14,283,000 [5],[7],[8],[9]
Rate 4.00% [1],[3],[4] 4.00% [5],[7],[8],[9]
Fair Value $ 12,284,000 [1],[3],[4] $ 15,211,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 4.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2026-06 [1],[3],[4] 2026-06 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 4.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2029-12 [1],[3],[4] 2029-12 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.56% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 8,154,000  
Rate [1],[3],[4] 4.56%  
Maturity [1],[3],[4] 2065-01  
Fair Value [1],[3],[4] $ 8,850,000  
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 5.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 7,799,000 [1],[3],[4] $ 8,424,000 [5],[7],[8],[9]
Rate 5.00% [1],[3],[4] 5.00% [5],[7],[8],[9]
Fair Value $ 8,680,000 [1],[3],[4] $ 9,497,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 5.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2043-09 [1],[3],[4] 2043-09 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 5.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2044-01 [1],[3],[4] 2044-01 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) 3.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 8,221,000 [1],[3],[4] $ 7,402,000 [5],[7],[8],[9]
Rate 3.50% [1],[3],[4] 3.50% [5],[7],[8],[9]
Fair Value $ 8,508,000 [1],[3],[4] $ 7,678,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) 3.50% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2030-02 [1],[3],[4] 2043-04 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) 3.50% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2043-06 [1],[3],[4] 2043-06 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.68% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 6,705,000 [1],[3],[4] $ 4,131,000 [5],[7],[8],[9]
Rate 4.68% [1],[3],[4] 4.68% [5],[7],[8],[9]
Maturity [5],[7],[8],[9]   2064-09
Fair Value $ 7,280,000 [1],[3],[4] $ 4,647,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.68% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [1],[3],[4] 2063-11  
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.68% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [1],[3],[4] 2064-09  
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.61% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 6,196,000 [1],[3],[4] $ 6,883,000 [5],[7],[8],[9]
Rate 4.61% [1],[3],[4] 4.61% [5],[7],[8],[9]
Fair Value $ 6,734,000 [1],[3],[4] $ 7,738,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.61% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2064-06 [1],[3],[4] 2064-06 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.61% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2064-11 [1],[3],[4] 2064-11 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.59% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 6,041,000 [1],[3],[4] $ 5,945,000 [5],[7],[8],[9]
Rate 4.59% [1],[3],[4] 4.59% [5],[7],[8],[9]
Maturity 2064-11 [1],[3],[4] 2064-11 [5],[7],[8],[9]
Fair Value $ 6,565,000 [1],[3],[4] $ 6,695,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (20 Year) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 6,114,000 [1],[3],[4] $ 6,663,000 [5],[7],[8],[9]
Rate 4.00% [1],[3],[4] 4.00% [5],[7],[8],[9]
Fair Value $ 6,558,000 [1],[3],[4] $ 7,213,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (20 Year) 4.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2033-11 [1],[3],[4] 2033-11 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (20 Year) 4.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2033-12 [1],[3],[4] 2033-12 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 3.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 6,256,000 [1],[3],[4] $ 20,140,000 [5],[7],[8],[9]
Rate 3.00% [1],[3],[4] 3.00% [5],[7],[8],[9]
Fair Value $ 6,266,000 [1],[3],[4] $ 20,425,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 3.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2043-01 [1],[3],[4] 2043-01 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 3.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2043-02 [1],[3],[4] 2043-05 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 3.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 5,859,000 [1],[3],[4] $ 2,990,000 [5],[7],[8],[9]
Rate 3.00% [1],[3],[4] 3.00% [5],[7],[8],[9]
Maturity [5],[7],[8],[9]   2028-03
Fair Value $ 6,054,000 [1],[3],[4] $ 3,114,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 3.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [1],[3],[4] 2028-03  
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 3.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [1],[3],[4] 2030-04  
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.62% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 4,888,000  
Rate [1],[3],[4] 4.62%  
Maturity [1],[3],[4] 2063-12  
Fair Value [1],[3],[4] $ 5,285,000  
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 5.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 4,713,000 [1],[3],[4] $ 5,131,000 [5],[7],[8],[9]
Rate 5.50% [1],[3],[4] 5.50% [5],[7],[8],[9]
Maturity 2039-10 [1],[3],[4] 2039-10 [5],[7],[8],[9]
Fair Value $ 5,248,000 [1],[3],[4] $ 5,741,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (15 Year) 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 4,564,000 [1],[3],[4] $ 5,916,000 [5],[7],[8],[9]
Rate 4.50% [1],[3],[4] 4.50% [5],[7],[8],[9]
Maturity 2026-04 [1],[3],[4] 2026-04 [5],[7],[8],[9]
Fair Value $ 4,914,000 [1],[3],[4] $ 6,232,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 3,764,000  
Rate [1],[3],[4] 4.50%  
Maturity [1],[3],[4] 2061-07  
Fair Value [1],[3],[4] $ 4,057,000  
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.75% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 3,748,000 [1],[3],[4] $ 4,181,000 [5],[7],[8],[9]
Rate 4.75% [1],[3],[4] 4.75% [5],[7],[8],[9]
Maturity 2061-01 [1],[3],[4] 2061-01 [5],[7],[8],[9]
Fair Value $ 3,877,000 [1],[3],[4] $ 4,457,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.63% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 3,406,000 [1],[3],[4] $ 3,809,000 [5],[7],[8],[9]
Rate 4.63% [1],[3],[4] 4.63% [5],[7],[8],[9]
Maturity 2064-10 [1],[3],[4] 2064-10 [5],[7],[8],[9]
Fair Value $ 3,704,000 [1],[3],[4] $ 4,295,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (30 Year) 3.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 3,402,000  
Rate [1],[3],[4] 3.50%  
Maturity [1],[3],[4] 2045-04  
Fair Value [1],[3],[4] $ 3,551,000  
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.80% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 3,376,000 [1],[3],[4] $ 3,680,000 [5],[7],[8],[9]
Rate 4.80% [1],[3],[4] 4.80% [5],[7],[8],[9]
Maturity 2061-02 [1],[3],[4] 2061-02 [5],[7],[8],[9]
Fair Value $ 3,504,000 [1],[3],[4] $ 3,933,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.49% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 3,129,000 [1],[3],[4] $ 3,300,000 [5],[7],[8],[9]
Rate 4.49% [1],[3],[4] 4.49% [5],[7],[8],[9]
Maturity 2064-11 [1],[3],[4] 2064-11 [5],[7],[8],[9]
Fair Value $ 3,376,000 [1],[3],[4] $ 3,698,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 5.49% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 2,966,000 [1],[3],[4] $ 3,487,000 [5],[7],[8],[9]
Rate 5.49% [1],[3],[4] 5.49% [5],[7],[8],[9]
Maturity 2060-04 [1],[3],[4] 2060-04 [5],[7],[8],[9]
Fair Value $ 3,151,000 [1],[3],[4] $ 3,811,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 2,780,000 [1],[3],[4] $ 2,836,000 [5],[7],[8],[9]
Rate 4.50% [1],[3],[4] 4.50% [5],[7],[8],[9]
Maturity 2044-05 [1],[3],[4] 2044-05 [5],[7],[8],[9]
Fair Value $ 3,031,000 [1],[3],[4] $ 3,131,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.64% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 2,680,000  
Rate [1],[3],[4] 4.64%  
Maturity [1],[3],[4] 2065-03  
Fair Value [1],[3],[4] $ 2,924,000  
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) 3.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 2,788,000 [1],[3],[4] $ 3,027,000 [5],[7],[8],[9]
Rate 3.00% [1],[3],[4] 3.00% [5],[7],[8],[9]
Maturity 2028-06 [1],[3],[4] 2028-06 [5],[7],[8],[9]
Fair Value $ 2,880,000 [1],[3],[4] $ 3,139,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 6.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 2,533,000 [1],[3],[4] $ 2,794,000 [5],[7],[8],[9]
Rate 6.00% [1],[3],[4] 6.00% [5],[7],[8],[9]
Fair Value $ 2,866,000 [1],[3],[4] $ 3,164,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 6.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2039-09 [1],[3],[4] 2039-09 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (30 Year) 6.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2040-02 [1],[3],[4] 2040-02 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 5.54% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 2,469,000 [1],[3],[4] $ 2,931,000 [5],[7],[8],[9]
Rate 5.54% [1],[3],[4] 5.54% [5],[7],[8],[9]
Maturity 2060-02 [1],[3],[4] 2060-02 [5],[7],[8],[9]
Fair Value $ 2,598,000 [1],[3],[4] $ 3,177,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 5.51% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 2,326,000 [1],[3],[4] $ 2,668,000 [5],[7],[8],[9]
Rate 5.51% [1],[3],[4] 5.51% [5],[7],[8],[9]
Maturity 2060-02 [1],[3],[4] 2060-02 [5],[7],[8],[9]
Fair Value $ 2,479,000 [1],[3],[4] $ 2,919,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (15 Year) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 1,988,000 [1],[3],[4] $ 2,561,000 [5],[7],[8],[9]
Rate 4.00% [1],[3],[4] 4.00% [5],[7],[8],[9]
Maturity 2029-02 [1],[3],[4] 2029-02 [5],[7],[8],[9]
Fair Value $ 2,121,000 [1],[3],[4] $ 2,728,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 6.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 1,608,000 [1],[3],[4] $ 1,849,000 [5],[7],[8],[9]
Rate 6.00% [1],[3],[4] 6.00% [5],[7],[8],[9]
Fair Value $ 1,807,000 [1],[3],[4] $ 2,084,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 6.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2039-04 [1],[3],[4] 2039-04 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 6.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2040-05 [1],[3],[4] 2040-05 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (20 Year) 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 1,352,000 [1],[3],[4] $ 1,510,000 [5],[7],[8],[9]
Rate 4.50% [1],[3],[4] 4.50% [5],[7],[8],[9]
Maturity 2033-12 [1],[3],[4] 2033-12 [5],[7],[8],[9]
Fair Value $ 1,471,000 [1],[3],[4] $ 1,652,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 3.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 1,139,000 [1],[3],[4] $ 10,130,000 [5],[7],[8],[9]
Rate 3.00% [1],[3],[4] 3.00% [5],[7],[8],[9]
Maturity [1],[3],[4] 2043-07  
Fair Value $ 1,140,000 [1],[3],[4] $ 10,271,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 3.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [5],[7],[8],[9]   2043-01
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 3.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [5],[7],[8],[9]   2043-04
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 5.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 879,000 [1],[3],[4] $ 1,298,000 [5],[7],[8],[9]
Rate 5.00% [1],[3],[4] 5.00% [5],[7],[8],[9]
Maturity 2044-07 [1],[3],[4] 2044-07 [5],[7],[8],[9]
Fair Value $ 964,000 [1],[3],[4] $ 1,444,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (30 Year) 5.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 689,000 [1],[3],[4] $ 851,000 [5],[7],[8],[9]
Rate 5.50% [1],[3],[4] 5.50% [5],[7],[8],[9]
Maturity 2033-08 [1],[3],[4] 2033-08 [5],[7],[8],[9]
Fair Value $ 764,000 [1],[3],[4] $ 954,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 126,000 [1],[3],[4] $ 245,000 [5],[7],[8],[9]
Rate 4.00% [1],[3],[4] 4.00% [5],[7],[8],[9]
Maturity 2037-06 [1],[3],[4] 2037-06 [5],[7],[8],[9]
Fair Value $ 130,000 [1],[3],[4] $ 260,000 [5],[7],[8],[9]
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [5],[7],[8],[9]   $ 2,238,000
Rate [5],[7],[8],[9]   4.00%
Fair Value [5],[7],[8],[9]   $ 2,398,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) 4.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [5],[7],[8],[9]   2043-07
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools (Other) 4.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity [5],[7],[8],[9]   2044-10
Principal And Interest - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association Pools (Other) 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [5],[7],[8],[9]   $ 5,526,000
Rate [5],[7],[8],[9]   4.50%
Maturity [5],[7],[8],[9]   2044-02
Fair Value [5],[7],[8],[9]   $ 6,108,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.66% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [5],[7],[8],[9]   $ 3,458,000
Rate [5],[7],[8],[9]   4.66%
Maturity [5],[7],[8],[9]   2063-01
Fair Value [5],[7],[8],[9]   $ 3,792,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.67% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [5],[7],[8],[9]   $ 3,290,000
Rate [5],[7],[8],[9]   4.67%
Maturity [5],[7],[8],[9]   2061-10
Fair Value [5],[7],[8],[9]   $ 3,551,000
Principal And Interest - Fixed Rate Agency Securities [Member] | Government National Mortgage Association Pools (Other) 4.65% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [5],[7],[8],[9]   $ 1,079,000
Rate [5],[7],[8],[9]   4.65%
Maturity [5],[7],[8],[9]   2061-11
Fair Value [5],[7],[8],[9]   $ 1,167,000
Interest Only - Fixed Rate Agency Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 1.00% [1],[2],[3],[4] 1.20% [5],[6],[7],[8],[9]
Fair Value $ 7,403,000 [1],[3],[4] $ 9,441,000 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 5.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 8,681,000  
Rate [1],[3],[4] 5.50%  
Maturity [1],[3],[4] 2043-11  
Fair Value [1],[3],[4] $ 1,603,000  
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 5.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 11,249,000 [1],[3],[4] $ 17,397,000 [5],[7],[8],[9]
Rate 5.00% [1],[3],[4] 5.00% [5],[7],[8],[9]
Fair Value $ 1,425,000 [1],[3],[4] $ 1,899,000 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 5.00% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2036-01 [1],[3],[4] 2036-01 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 5.00% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2040-05 [1],[3],[4] 2040-05 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 8,889,000 [1],[3],[4] $ 30,581,000 [5],[7],[8],[9]
Rate 4.50% [1],[3],[4] 4.50% [5],[7],[8],[9]
Fair Value $ 963,000 [1],[3],[4] $ 3,946,000 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 4.50% [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2020-12 [1],[3],[4] 2020-12 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 4.50% [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2043-05 [1],[3],[4] 2043-06 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation 3.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 5,977,000 [1],[3],[4] $ 6,935,000 [5],[7],[8],[9]
Rate 3.50% [1],[3],[4] 3.50% [5],[7],[8],[9]
Maturity 2032-12 [1],[3],[4] 2032-12 [5],[7],[8],[9]
Fair Value $ 869,000 [1],[3],[4] $ 1,001,000 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation 5.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 4,884,000 [1],[3],[4] $ 7,621,000 [5],[7],[8],[9]
Rate 5.00% [1],[3],[4] 5.00% [5],[7],[8],[9]
Maturity 2040-03 [1],[3],[4] 2040-03 [5],[7],[8],[9]
Fair Value $ 519,000 [1],[3],[4] $ 815,000 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 3.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 3,909,000 [1],[3],[4] $ 4,691,000 [5],[7],[8],[9]
Rate 3.00% [1],[3],[4] 3.00% [5],[7],[8],[9]
Maturity 2041-09 [1],[3],[4] 2041-09 [5],[7],[8],[9]
Fair Value $ 421,000 [1],[3],[4] $ 554,000 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 4.75% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 2,019,000 [1],[3],[4] $ 2,142,000 [5],[7],[8],[9]
Rate 4.75% [1],[3],[4] 4.75% [5],[7],[8],[9]
Maturity 2040-07 [1],[3],[4] 2040-07 [5],[7],[8],[9]
Fair Value $ 378,000 [1],[3],[4] $ 461,000 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 6.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 1,544,000  
Rate [1],[3],[4] 6.00%  
Maturity [1],[3],[4] 2038-06  
Fair Value [1],[3],[4] $ 330,000  
Interest Only - Fixed Rate Agency Securities [Member] | Government National Mortgage Association 5.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 3,782,000  
Rate [1],[3],[4] 5.00%  
Maturity [1],[3],[4] 2037-05  
Fair Value [1],[3],[4] $ 311,000  
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 5.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 1,651,000 [1],[3],[4] $ 2,242,000 [5],[7],[8],[9]
Rate 5.50% [1],[3],[4] 5.50% [5],[7],[8],[9]
Maturity 2040-10 [1],[3],[4] 2040-10 [5],[7],[8],[9]
Fair Value $ 239,000 [1],[3],[4] $ 285,000 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 1,346,000 [1],[3],[4] $ 1,826,000 [5],[7],[8],[9]
Rate 4.00% [1],[3],[4] 4.00% [5],[7],[8],[9]
Maturity 2039-05 [1],[3],[4] 2039-05 [5],[7],[8],[9]
Fair Value $ 219,000 [1],[3],[4] $ 287,000 [5],[7],[8],[9]
Interest Only - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation 5.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 1,109,000 [1],[3],[4] $ 1,609,000 [5],[7],[8],[9]
Rate 5.50% [1],[3],[4] 5.50% [5],[7],[8],[9]
Maturity 2039-01 [1],[3],[4] 2039-01 [5],[7],[8],[9]
Fair Value $ 126,000 [1],[3],[4] $ 193,000 [5],[7],[8],[9]
TBA - Fixed Rate Agency Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 13.26% [1],[2],[3],[4] 9.18% [5],[6],[7],[8],[9]
Current Principal/Notional Amount $ 94,602,000 $ 71,598,000
Fair Value 98,009,000 [1],[3],[4] 72,410,000 [5],[7],[8],[9]
TBA - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association (30 Year) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 40,262,000  
Rate [1],[3],[4] 4.00%  
Maturity [1],[3],[4] 2016-01  
Fair Value [1],[3],[4] $ 42,607,000  
TBA - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation (30 Year) 3.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 26,600,000  
Rate [1],[3],[4] 3.50%  
Maturity [1],[3],[4] 2016-01  
Fair Value [1],[3],[4] $ 27,394,000  
TBA - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation (30 Year) 3.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 15,040,000  
Rate [1],[3],[4] 3.00%  
Maturity [1],[3],[4] 2016-01  
Fair Value [1],[3],[4] $ 15,022,000  
TBA - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association (15 Year) 2.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 9,800,000  
Rate [1],[3],[4] 2.50%  
Maturity 2016-01  
Fair Value [1],[3],[4] $ 9,879,000  
TBA - Fixed Rate Agency Securities [Member] | Government National Mortgage Association (30 Year) 4.50% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 2,200,000  
Rate [1],[3],[4] 4.50%  
Maturity [1],[3],[4] 2016-01  
Fair Value [1],[3],[4] $ 2,364,000  
TBA - Fixed Rate Agency Securities [Member] | Government National Mortgage Association (30 year) 4.00% [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [1],[3],[4] $ 700,000  
Rate [1],[3],[4] 4.00%  
Maturity [1],[3],[4] 2016-01  
Fair Value [1],[3],[4] $ 743,000  
TBA - Fixed Rate Agency Securities [Member] | Federal National Mortgage Association (30 Year) [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [5],[7],[8],[9]   $ 44,478,000
Rate [5],[7],[8],[9]   3.00%
Maturity [5],[7],[8],[9]   2015-01
Fair Value [5],[7],[8],[9]   $ 45,015,000
TBA - Fixed Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation (30 Year) [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [5],[7],[8],[9]   $ 27,120,000
Rate [5],[7],[8],[9]   3.00%
Maturity [5],[7],[8],[9]   2015-01
Fair Value [5],[7],[8],[9]   $ 27,395,000
Fixed Rate Agency Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 138.57% [1],[2],[3],[4] 158.20% [5],[6],[7],[8],[9]
Fair Value $ 1,023,974,000 [1],[3],[4] $ 1,247,493,000 [5],[7],[8],[9]
Investment Owned, at Cost $ 1,023,479,000 [1],[3],[4] $ 1,230,414,000 [5],[7],[8],[9]
Principal And Interest - Floating Rate Agency Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 2.58% [1],[2],[3],[4] 2.62% [5],[6],[7],[8],[9]
Fair Value $ 19,091,000 [1],[3],[4] $ 20,647,000 [5],[7],[8],[9]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal National Mortgage Association Pools [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 9,490,000 [1],[3],[4] 6,265,000 [5],[7],[8],[9]
Fair Value $ 9,990,000 [1],[3],[4] $ 6,692,000 [5],[7],[8],[9]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal National Mortgage Association Pools [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 2.05% [1],[3],[4] 5.04% [5],[7],[8],[9]
Maturity 2035-09 [1],[3],[4] 2035-09 [5],[7],[8],[9]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal National Mortgage Association Pools [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 6.04% [1],[3],[4] 6.05% [5],[7],[8],[9]
Maturity 2045-05 [1],[3],[4] 2037-09 [5],[7],[8],[9]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 6,287,000 [1],[3],[4] $ 9,737,000 [5],[7],[8],[9]
Fair Value $ 6,625,000 [1],[3],[4] $ 10,282,000 [5],[7],[8],[9]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 2.61% [1],[3],[4] 2.36% [5],[7],[8],[9]
Maturity 2037-06 [1],[3],[4] 2037-06 [5],[7],[8],[9]
Principal And Interest - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation Pools [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 5.94% [1],[3],[4] 5.94% [5],[7],[8],[9]
Maturity 2044-05 [1],[3],[4] 2044-05 [5],[7],[8],[9]
Principal And Interest - Floating Rate Agency Securities [Member] | Government National Mortgage Association Pools [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 2,349,000 [1],[3],[4] $ 3,404,000 [5],[7],[8],[9]
Rate 2.55% [1],[3],[4] 2.47% [5],[7],[8],[9]
Maturity 2064-11 [1],[3],[4] 2064-11 [5],[7],[8],[9]
Fair Value $ 2,476,000 [1],[3],[4] $ 3,673,000 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 2.37% [1],[2],[3],[4] 2.78% [5],[6],[7],[8],[9]
Fair Value $ 17,515,000 [1],[3],[4] $ 21,944,000 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member] | Government National Mortgage Association [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 203,125,000 [1],[3],[4] 183,794,000 [5],[7],[8],[9]
Fair Value $ 12,186,000 [1],[3],[4] $ 13,591,000 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member] | Government National Mortgage Association [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 0.43% [1],[3],[4] 0.40% [5],[7],[8],[9]
Maturity 2042-11 [1],[3],[4] 2042-11 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member] | Government National Mortgage Association [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 6.35% [1],[3],[4] 6.58% [5],[7],[8],[9]
Maturity 2063-10 [1],[3],[4] 2063-10 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member] | Federal National Mortgage Association [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 18,517,000 [1],[3],[4] $ 28,251,000 [5],[7],[8],[9]
Fair Value $ 2,718,000 [1],[3],[4] $ 4,508,000 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member] | Federal National Mortgage Association [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 5.50% [1],[3],[4] 5.50% [5],[7],[8],[9]
Maturity 2033-06 [1],[3],[4] 2035-04 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member] | Federal National Mortgage Association [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 7.13% [1],[3],[4] 6.58% [5],[7],[8],[9]
Maturity 2041-12 [1],[3],[4] 2043-07 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member] | Resecuritization of Government National Mortgage Association [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 20,272,000 [1],[3],[4],[10] $ 21,145,000 [5],[7],[8],[9],[11]
Rate 4.31% [1],[3],[4],[10] 4.34% [5],[7],[8],[9],[11]
Maturity 2060-08 [1],[3],[4],[10] 2060-08 [5],[7],[8],[9],[11]
Fair Value $ 1,486,000 [1],[3],[4],[10] $ 1,973,000 [5],[7],[8],[9],[11]
Interest Only - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 6,446,000 [1],[3],[4] 13,048,000 [5],[7],[8],[9]
Fair Value $ 1,125,000 [1],[3],[4] $ 1,872,000 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 5.67% [1],[3],[4] 5.84% [5],[7],[8],[9]
Maturity 2036-03 [1],[3],[4] 2036-03 [5],[7],[8],[9]
Interest Only - Floating Rate Agency Securities [Member] | Federal Home Loan Mortgage Corporation [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 6.30% [1],[3],[4] 6.47% [5],[7],[8],[9]
Maturity 2039-08 [1],[3],[4] 2039-08 [5],[7],[8],[9]
Floating Rate Agency Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 4.95% [1],[2],[3],[4] 5.40% [5],[6],[7],[8],[9]
Fair Value $ 36,606,000 [1],[3],[4] $ 42,591,000 [5],[7],[8],[9]
Investment Owned, at Cost $ 36,192,000 [1],[3],[4] $ 41,787,000 [5],[7],[8],[9]
Agency Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 143.52% [1],[2],[3],[4] 163.60% [5],[6],[7],[8],[9]
Fair Value $ 1,060,580,000 [1],[3],[4] $ 1,290,084,000 [5],[7],[8],[9]
Investment Owned, at Cost $ 1,059,671,000 [1],[3],[4] $ 1,272,201,000 [5],[7],[8],[9]
Principal And Interest - Private Label Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 38.20% [2],[3],[4] 76.95% [6],[7],[8],[9]
Fair Value $ 282,301,000 [3],[4] $ 606,757,000 [7],[8],[9]
Investment Owned, at Cost $ 280,475,000 [3],[4] $ 571,834,000 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 32.11% [2],[3],[4] 71.67% [6],[7],[8],[9]
Fair Value $ 237,325,000 [3],[4] $ 565,117,000 [7],[8],[9]
Investment Owned, at Cost $ 229,780,000 [3],[4] $ 526,764,000 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 6.09% [2],[3],[4] 5.28% [6],[7],[8],[9]
Fair Value $ 44,976,000 [3],[4] $ 41,640,000 [7],[8],[9]
Investment Owned, at Cost 50,695,000 [3],[4] 45,070,000 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 84,045,000 [3],[4] 117,877,000 [7],[8],[9]
Fair Value 24,456,000 [3],[4] 39,240,000 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Mortgage-related Commercial [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 7,821,000 [3],[4] 12,784,000 [7],[8],[9]
Fair Value 7,812,000 [3],[4] 12,837,000 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 380,261,000 [3],[4] 799,083,000 [7],[8],[9]
Fair Value 212,869,000 [3],[4] 525,877,000 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Mortgage-related Residential [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 50,851,000 [3],[4] 33,294,000 [7],[8],[9]
Fair Value $ 37,164,000 [3],[4] $ 28,803,000 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 3.00% [3],[4] 3.00% [7],[8],[9]
Maturity 2045-07 [3],[4] 2045-07 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Commercial [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Rate 0.00% [3],[4] 0.00% [7],[8],[9]
Maturity 2017-06 [3],[4] 2015-07 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 0.00% [3],[4] 0.00% [7],[8],[9]
Maturity 2019-05 [3],[4] 2019-05 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Residential [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Rate 0.00% [3],[4] 0.34% [7],[8],[9]
Maturity 2025-06 [3],[4] 2038-08 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 4.40% [3],[4] 5.40% [7],[8],[9]
Maturity 2048-02 [3],[4] 2049-12 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Commercial [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Rate 11.00% [3],[4] 12.25% [7],[8],[9]
Maturity 2019-06 [3],[4] 2024-03 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 9.35% [3],[4] 9.35% [7],[8],[9]
Maturity 2046-09 [3],[4] 2047-07 [7],[8],[9]
Principal And Interest - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Residential [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Rate 5.32% [3],[4] 4.41% [7],[8],[9]
Maturity 2050-03 [3],[4] 2061-01 [7],[8],[9]
Principal Only - Private Label Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 0.51% [2],[3],[4] 0.41% [6],[7],[8],[9]
Fair Value $ 3,749,000 [3],[4] $ 3,248,000 [7],[8],[9]
Investment Owned, at Cost 3,024,000 [3],[4] 2,737,000 [7],[8],[9]
Principal Only - Private Label Securities [Member] | Various Issuer [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 5,800,000 [3],[4] $ 5,800,000 [7],[8],[9]
Rate 0.00% [3],[4] 0.00% [7],[8],[9]
Maturity 2030-08 [3],[4] 2030-08 [7],[8],[9]
Fair Value $ 3,749,000 [3],[4] $ 3,248,000 [7],[8],[9]
Interest Only - Private Label Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 0.41% [2],[3],[4] 0.31% [6],[7],[8],[9]
Fair Value $ 3,012,000 [3],[4] $ 2,423,000 [7],[8],[9]
Investment Owned, at Cost 2,110,000 [3],[4] 1,602,000 [7],[8],[9]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 27,254,000 [3],[4] 17,666,000 [7],[8],[9]
Fair Value 1,877,000 [3],[4] 1,234,000 [7],[8],[9]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 41,097,000 [3],[4] 47,557,000 [7],[8],[9]
Fair Value $ 1,135,000 [3],[4] $ 1,189,000 [7],[8],[9]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 1.43% [3],[4] 1.42% [7],[8],[9]
Maturity 2047-10 [3],[4] 2047-10 [7],[8],[9]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 0.50% [3],[4] 0.50% [7],[8],[9]
Maturity 2044-06 [3],[4] 2044-06 [7],[8],[9]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 1.57% [3],[4] 1.45% [7],[8],[9]
Maturity 2048-02 [3],[4] 2047-12 [7],[8],[9]
Interest Only - Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 2.00% [3],[4] 2.00% [7],[8],[9]
Maturity 2047-09 [3],[4] 2047-09 [7],[8],[9]
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],[9]
Fair Value $ 0 [3],[4] $ 0 [7],[8],[9]
Investment Owned, at Cost 273,000 [3],[4] 302,000 [7],[8],[9]
Other Private Label Securities [Member] | Various Issuer [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 0 [3],[4] $ 0 [7],[8],[9]
Rate 0.00% [3],[4] 0.00% [7],[8],[9]
Fair Value $ 0 [3],[4] $ 0 [7],[8],[9]
Other Private Label Securities [Member] | Various Issuer [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 100,882,000 [3],[4] $ 111,629,000 [7],[8],[9]
Rate 0.00% [3],[4] 0.00% [7],[8],[9]
Maturity 2037-06 [3],[4] 2037-06 [7],[8],[9]
Fair Value $ 0 [3],[4] $ 0 [7],[8],[9]
Other Private Label Securities [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2045-07 [3],[4] 2045-07 [7],[8],[9]
Other Private Label Securities [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Maturity 2048-02 [3],[4] 2047-10 [7],[8],[9]
Private Label Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 39.12% [2],[3],[4] 77.67% [6],[7],[8],[9]
Fair Value $ 289,062,000 [3],[4] $ 612,428,000 [7],[8],[9]
Investment Owned, at Cost $ 285,882,000 [3],[4] $ 576,475,000 [7],[8],[9]
Mortgage-Backed Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 182.64% [2],[3],[4] 241.27% [6],[7],[8],[9]
Fair Value $ 1,349,642,000 [3],[4] $ 1,902,512,000 [7],[8],[9]
Investment Owned, at Cost $ 1,345,553,000 [3],[4] $ 1,848,676,000 [7],[8],[9]
Collateralized Loan Obligations [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 6.22% [2],[3],[4] 15.47% [6],[7],[8],[9]
Fair Value $ 45,974,000 [3],[4] $ 121,994,000 [7],[8],[9]
Investment Owned, at Cost $ 52,576,000 [3],[4] $ 124,562,000 [7],[8],[9]
Collateralized Loan Obligations [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 2.86% [2],[3],[4] 13.05% [6],[7],[8],[9]
Fair Value $ 21,120,000 [3],[4] $ 102,883,000 [7],[8],[9]
Investment Owned, at Cost $ 26,341,000 [3],[4] $ 104,547,000 [7],[8],[9]
Collateralized Loan Obligations [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 3.36% [2],[3],[4] 2.42% [6],[7],[8],[9]
Fair Value $ 24,854,000 [3],[4] $ 19,111,000 [7],[8],[9]
Investment Owned, at Cost 26,235,000 [3],[4] 20,015,000 [7],[8],[9]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 67,640,000 [3],[4] 128,188,000 [7],[8],[9]
Fair Value 21,120,000 [3],[4] 102,883,000 [7],[8],[9]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 35,472,000 [3],[4] 19,786,000 [7],[8],[9]
Fair Value $ 24,854,000 [3],[4] $ 19,111,000 [7],[8],[9]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Minimum [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 0.00% [3],[4] 0.00% [7],[8],[9]
Maturity 2016-05 [3],[4] 2017-02 [7],[8],[9]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Minimum [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Rate 0.00% [3],[4] 1.73% [7],[8],[9]
Maturity 2022-01 [3],[4] 2017-03 [7],[8],[9]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Maximum [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 9.15% [3],[4] 9.73% [7],[8],[9]
Maturity 2068-09 [3],[4] 2068-09 [7],[8],[9]
Collateralized Loan Obligations [Member] | Various Issuer [Member] | Maximum [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Rate 4.43% [3],[4] 4.00% [7],[8],[9]
Maturity 2056-12 [3],[4] 2023-03 [7],[8],[9]
Consumer loans and asset-backed securities backed by consumer loans [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 15.61% [2],[3],[4],[12] 3.08% [6],[7],[8],[9],[13]
Fair Value $ 115,376,000 [3],[4],[12] $ 24,294,000 [7],[8],[9],[13]
Investment Owned, at Cost $ 115,624,000 [3],[4],[12] $ 24,824,000 [7],[8],[9],[13]
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 15.22% [2],[3],[4],[12] 2.59% [6],[7],[8],[9],[13]
Fair Value $ 112,471,000 [3],[4],[12] $ 20,434,000 [7],[8],[9],[13]
Investment Owned, at Cost $ 112,840,000 [3],[4],[12] $ 20,549,000 [7],[8],[9],[13]
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 0.39% [2],[3],[4],[12] 0.49% [6],[7],[8],[9],[13]
Fair Value $ 2,905,000 [3],[4],[12] $ 3,860,000 [7],[8],[9],[13]
Investment Owned, at Cost 2,784,000 [3],[4],[12] 4,275,000 [7],[8],[9],[13]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | Consumer [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 109,763,000 [3],[4],[12],[14] 17,624,000 [7],[8],[9],[13]
Fair Value 112,471,000 [3],[4],[12],[14] 20,434,000 [7],[8],[9],[13]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | Consumer [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 2,163,000 [3],[4],[12] $ 3,860,000 [7],[8],[9],[13]
Rate 0.00% [3],[4],[12] 0.00% [7],[8],[9],[13]
Maturity 2024-08 [3],[4],[12] 2024-08 [7],[8],[9],[13]
Fair Value $ 2,905,000 [3],[4],[12] $ 3,860,000 [7],[8],[9],[13]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | Minimum [Member] | Consumer [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 5.50% [3],[4],[12],[14] 0.00% [7],[8],[9],[13]
Maturity 2016-01 [3],[4],[12],[14] 2015-06 [7],[8],[9],[13]
Consumer loans and asset-backed securities backed by consumer loans [Member] | Various Issuer [Member] | Maximum [Member] | Consumer [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 49.00% [3],[4],[12],[14] 49.00% [7],[8],[9],[13]
Maturity 2020-12 [3],[4],[12],[14] 2019-07 [7],[8],[9],[13]
Corporate Debt [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 3.66% [2],[3],[4] 5.41% [6],[7],[8],[9]
Fair Value $ 27,028,000 [3],[4] $ 42,708,000 [7],[8],[9]
Investment Owned, at Cost $ 34,786,000 [3],[4] 43,585,000 [7],[8],[9]
Corporate Debt [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity [2],[3],[4] 2.50%  
Fair Value [3],[4] $ 18,452,000  
Investment Owned, at Cost [3],[4] $ 25,815,000  
Corporate Debt [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity [2],[3],[4] 1.16%  
Fair Value [3],[4] $ 8,576,000  
Investment Owned, at Cost [3],[4] 8,971,000  
Corporate Debt [Member] | Various Issuer [Member] | Basic Materials [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount $ 5,720,000 [3],[4] $ 5,440,000 [7],[8],[9]
Rate 11.75% [3],[4] 9.00% [7],[8],[9]
Maturity 2019-01 [3],[4] 2019-11 [7],[8],[9]
Fair Value $ 889,000 [3],[4] $ 5,114,000 [7],[8],[9]
Corporate Debt [Member] | Various Issuer [Member] | Communications [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [7],[8],[9]   15,255,000
Fair Value [7],[8],[9]   14,671,000
Corporate Debt [Member] | Various Issuer [Member] | Communications [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [3],[4] $ 7,885,000  
Rate [3],[4] 14.00%  
Maturity [3],[4] 2018-10  
Fair Value [3],[4] $ 8,083,000  
Corporate Debt [Member] | Various Issuer [Member] | Consumer [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 3,985,000 [3],[4] 6,543,000 [7],[8],[9]
Fair Value 1,282,000 [3],[4] 5,867,000 [7],[8],[9]
Corporate Debt [Member] | Various Issuer [Member] | Consumer [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [3],[4] $ 16,443,000  
Rate [3],[4] 0.00%  
Maturity [3],[4] 2016-12  
Fair Value [3],[4] $ 493,000  
Corporate Debt [Member] | Various Issuer [Member] | Diversified [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [7],[8],[9]   $ 2,793,000
Rate [7],[8],[9]   7.50%
Maturity [7],[8],[9]   2020-05
Fair Value [7],[8],[9]   $ 2,779,000
Corporate Debt [Member] | Various Issuer [Member] | Energy [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 14,193,000 [3],[4] 7,475,000 [7],[8],[9]
Fair Value 2,459,000 [3],[4] 5,877,000 [7],[8],[9]
Corporate Debt [Member] | Various Issuer [Member] | Financial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [3],[4] $ 54,000  
Rate [3],[4] 10.25%  
Maturity [3],[4] 2023-08  
Fair Value [3],[4] $ 52,000  
Corporate Debt [Member] | Various Issuer [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 14,250,000 [3],[4] $ 8,500,000 [7],[8],[9]
Rate [7],[8],[9]   15.00%
Maturity [7],[8],[9]   2019-10
Fair Value $ 13,770,000 [3],[4] $ 8,400,000 [7],[8],[9]
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | Communications [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate [7],[8],[9]   7.75%
Maturity [7],[8],[9]   2016-12
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | Consumer [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 0.00% [3],[4] 5.25% [7],[8],[9]
Maturity 2020-05 [3],[4] 2016-06 [7],[8],[9]
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | Energy [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 6.50% [3],[4] 7.00% [7],[8],[9]
Maturity 2018-09 [3],[4] 2017-01 [7],[8],[9]
Corporate Debt [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate [3],[4] 15.00%  
Maturity [3],[4] 2017-12  
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | Communications [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate [7],[8],[9]   14.00%
Maturity [7],[8],[9]   2019-06
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | Consumer [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 10.00% [3],[4] 11.50% [7],[8],[9]
Maturity 2020-07 [3],[4] 2021-09 [7],[8],[9]
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | Energy [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 12.25% [3],[4] 12.25% [7],[8],[9]
Maturity 2020-02 [3],[4] 2019-06 [7],[8],[9]
Corporate Debt [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate [3],[4] 20.00%  
Maturity [3],[4] 2019-10  
Mortgage Loans [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 11.97% [2],[3],[4],[12] 7.08% [6],[7],[8],[9],[13]
Fair Value $ 88,488,000 [3],[4],[12] $ 55,791,000 [7],[8],[9],[13]
Investment Owned, at Cost 89,009,000 [3],[4],[12] 55,664,000 [7],[8],[9],[13]
Mortgage Loans [Member] | Various Issuer [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 77,556,000 [3],[4],[12],[15] 32,519,000 [7],[8],[9],[13],[16]
Fair Value 66,399,000 [3],[4],[12],[15] 28,309,000 [7],[8],[9],[13],[16]
Mortgage Loans [Member] | Various Issuer [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount 30,267,000 [3],[4],[12],[17] $ 44,336,000 [7],[8],[9],[13]
Rate [7],[8],[9],[13]   0.00%
Fair Value $ 22,089,000 [3],[4],[12],[17] $ 27,482,000 [7],[8],[9],[13]
Mortgage Loans [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 2.54% [3],[4],[12],[15] 0.00% [7],[8],[9],[13],[16]
Maturity 2016-04 [3],[4],[12],[15] 2015-01 [7],[8],[9],[13],[16]
Mortgage Loans [Member] | Various Issuer [Member] | Minimum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate [3],[4],[12],[17] 1.00%  
Maturity 2021-07 [3],[4],[12],[17] 2018-02 [7],[8],[9],[13]
Mortgage Loans [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate 12.00% [3],[4],[12],[15] 10.00% [7],[8],[9],[13],[16]
Maturity 2045-07 [3],[4],[12],[15] 2017-11 [7],[8],[9],[13],[16]
Mortgage Loans [Member] | Various Issuer [Member] | Maximum [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Rate [3],[4],[12],[17] 13.50%  
Maturity 2055-09 [3],[4],[12],[17] 2054-10 [7],[8],[9],[13]
Real Estate Owned [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 1.70% [2],[3],[4],[12],[18] 1.10% [6],[7],[8],[9],[13],[19]
Fair Value $ 12,522,000 [3],[4],[12],[18] $ 8,635,000 [7],[8],[9],[13],[19]
Investment Owned, at Cost 12,254,000 [3],[4],[12],[18] 8,748,000 [7],[8],[9],[13],[19]
Real Estate Owned [Member] | Single-Family Houses [Member] | Real estate-related [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Fair Value $ 4,090,000 [3],[4],[12],[18] $ 6,591,000 [7],[8],[9],[13],[19]
Number of Real Estate Properties 28 [3],[4],[12],[18] 50 [7],[8],[9],[13],[19]
Real Estate Owned [Member] | Commercial Property [Member] | Real estate-related [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Fair Value $ 8,432,000 [3],[4],[12],[18] $ 2,044,000 [7],[8],[9],[13],[19]
Number of Real Estate Properties 2 [3],[4],[12],[18] 1 [7],[8],[9],[13],[19]
Private Corporate Equity Investments [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 2.99% [2],[3],[4] 1.84% [6],[7],[8],[9]
Fair Value $ 22,088,000 [3],[4] $ 14,512,000 [7],[8],[9]
Investment Owned, at Cost $ 22,598,000 [3],[4] 14,717,000 [7],[8],[9]
Private Corporate Equity Investments [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity [2],[3],[4] 2.99%  
Fair Value [3],[4] $ 22,088,000  
Investment Owned, at Cost [3],[4] $ 22,598,000  
Private Corporate Equity Investments [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity [2],[3],[4] 0.00%  
Fair Value [3],[4] $ 0  
Private Corporate Equity Investments [Member] | Non-Exchange Traded Corporate Equity [Member] | Consumer [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Fair Value $ 3,032,000 [3],[4] $ 2,090,000 [7],[8],[9]
Investment Owned, Balance, Shares 1,592 [3],[4] 32 [7],[8],[9]
Private Corporate Equity Investments [Member] | Non-Exchange Traded Corporate Equity [Member] | Consumer [Member] | Europe [Member]    
Schedule of Investments [Line Items]    
Fair Value [3],[4] $ 0  
Investment Owned, Balance, Shares [3],[4] 125  
Private Corporate Equity Investments [Member] | Non-Exchange Traded Corporate Equity [Member] | Diversified [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Fair Value $ 2,389,000 [3],[4] $ 770,000 [7],[8],[9]
Investment Owned, Balance, Shares 160 [3],[4] 56 [7],[8],[9]
Private Corporate Equity Investments [Member] | Non-Exchange Traded Corporate Equity [Member] | Technology [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Fair Value [3],[4] $ 741,000  
Investment Owned, Balance, Shares [3],[4] 99  
Private Corporate Equity Investments [Member] | Non-Exchange Traded Preferred Equity Investment in Commercial Mortgage-related Private Partnership | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Fair Value $ 7,687,000 [3],[4] $ 6,241,000 [7],[8],[9]
Investment Owned, Balance, Shares 8,171 [3],[4] 6,241 [7],[8],[9]
Private Corporate Equity Investments [Member] | Non-controlling Interest in Mortgage-related Private Partnership [Member] | Mortgage-related Commercial [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Fair Value $ 2,871,000 [3],[4] $ 2,673,000 [7],[8],[9]
Private Corporate Equity Investments [Member] | Non-Exchange Traded Preferred Equity Investment in Mortgage Originators [Member] | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Fair Value $ 4,325,000 [3],[4] $ 2,500,000 [7],[8],[9]
Investment Owned, Balance, Shares 9,482 [3],[4] 7,657 [7],[8],[9]
Private Corporate Equity Investments [Member] | Non-Exchange Traded Equity Investment in Mortgage Originator | Mortgage-related Residential [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Fair Value $ 1,043,000 [3],[4] $ 238,000 [7],[8],[9]
Investment Owned, Balance, Shares 7,479 [3],[4] 728 [7],[8],[9]
US Treasury Securities [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity [6],[7],[8],[9]   0.21%
Fair Value [7],[8],[9]   $ 1,636,000
Investment Owned, at Cost [7],[8],[9]   1,550,000
US Treasury Securities [Member] | US Treasury Bond Securities [Member] | Government [Member] | North America [Member]    
Schedule of Investments [Line Items]    
Current Principal/Notional Amount [7],[8],[9]   $ 1,560,000
Rate [7],[8],[9]   3.00%
Maturity [7],[8],[9]   2044-11
Fair Value [7],[8],[9]   $ 1,636,000
Long Investments [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 224.79% [2],[3],[4] 275.46% [6],[7],[8],[9]
Fair Value $ 1,661,118,000 [3],[4] $ 2,172,082,000 [7],[8],[9]
Investment Owned, at Cost $ 1,672,400,000 [3],[4] $ 2,122,326,000 [7],[8],[9]
Long Investments [Member] | Government National Mortgage Association [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 18.91% 9.33%
Long Investments [Member] | Federal National Mortgage Association [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 77.17% 100.30%
Long Investments [Member] | Federal Home Loan Mortgage Corporation [Member]    
Schedule of Investments [Line Items]    
Investment owned as a percentage of equity 47.44% 53.97%
[1] At December 31, 2015, 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 77.17%, 47.44%, and 18.91% of 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 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 143.52%A/A/A 0.32%Baa/BBB/BBB 1.07%Ba/BB/BB or below 34.89%Unrated 44.99%
[5] At December 31, 2014, 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 100.30%, 53.97%, and 9.33% of equity, respectively.
[6] Classification percentages are based on Total Equity.
[7] Conformed to current period presentation.
[8] See Note 2 and Note 3 in Notes to Consolidated Financial Statements.
[9] 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 163.60%A/A/A 0.98%Baa/BBB/BBB 5.62%Ba/BB/BB or below 80.65%Unrated 24.61%
[10] Private trust 100% backed by interest in Government National Mortgage Association collateralized mortgage obligation certificates.
[11] Private trust 100% backed by interest in Government National Mortgage Association collateralized mortgage obligation certificates.
[12] Loans and real estate owned are beneficially owned by the Company through participation certificates in the various trusts that hold such investments.
[13] Loans and real estate owned are beneficially owned by the Company through participation certificates in the various trusts that hold such investments.
[14] Includes investments in participation certificates related to loans held in a trust owned by a related party of Ellington Financial Management LLC. Through its participation certificates, the Company has beneficial interests in the cash flows of the underlying loans held by the trust. At December 31, 2015 loans held in the related party trust for which the Company has beneficial interests in the residual cash flows, totaled $3.8 million.
[15] Includes non-performing commercial loans in the amount of $22.6 million whereby principal and/or interest is past due and a maturity date is not applicable.
[16] Includes non-performing commercial loans in the amount of $11.3 million whereby principal and/or interest is past due and a maturity date is not applicable.
[17] As of December 31, 2015, the Company had residential mortgage loans that were in the process of foreclosure with a fair value of $5.9 million.
[18] Number of properties not shown in thousands, represents actual number of properties owned.
[19] Number of properties not shown in thousands, represents actual number of properties owned.