Valuation (Schedule Of Financial Instruments) (Details) - USD ($) $ in Thousands		Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-	[1]	$ 28,165	$ 35,595
Fair value repurchase agreements	[1]	155,949	184,819
Investments sold short, at fair value-		(642,240)	(584,896)
Financial derivatives–liabilities, at fair value-	[1]	(36,273)	(18,687)
Other secured borrowings, at fair value		125,105	0
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments, financial derivatives–assets, and repurchase agreements, at fair value		2,255,821	1,725,440
Total investments sold short, financial derivatives–liabilities, and other secured borrowings, at fair value		(803,618)	(603,583)
Fair Value, Measurements, Recurring [Member] | Other secured borrowings [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other secured borrowings, at fair value		(125,105)
Fair Value, Measurements, Recurring [Member] | Investments Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(642,240)	(584,896)
Fair Value, Measurements, Recurring [Member] | Investments Sold Short [Member] | Agency residential mortgage-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(460,189)	(404,728)
Fair Value, Measurements, Recurring [Member] | Investments Sold Short [Member] | Government debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(90,149)	(132,442)
Fair Value, Measurements, Recurring [Member] | Investments Sold Short [Member] | Corporate Debt Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(55,211)	(39,572)
Fair Value, Measurements, Recurring [Member] | Investments Sold Short [Member] | Common Stock Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(36,691)	(8,154)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(36,273)	(18,687)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			(256)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(12,367)	(2,840)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(15,930)	(6,654)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(980)	(2,899)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(6,015)	(5,162)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			(304)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member] | Futures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(508)	(69)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member] | Forwards [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(473)	(472)
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Liabilities [Member] | Mortgage Loan Purchase Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			(31)
Fair Value, Measurements, Recurring [Member] | Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents		26,500	90,000
Fair Value, Measurements, Recurring [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		2,071,707	1,505,026
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Agency residential mortgage-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		995,514	897,967
Fair Value, Measurements, Recurring [Member] | Investments [Member] | US Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-			5,419
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Private Label Residential Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		259,666	143,608
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Private Label Commercial Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		40,745	43,268
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Commercial Mortgage Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		108,301	61,129
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Residential Mortgage Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		182,472	84,290
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Collateralized Loan Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		210,816	44,956
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Consumer loans and asset-backed securities backed by consumer loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		135,258	107,157	[2]
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Corporate Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		75,193	80,095
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		26,277	3,349
Fair Value, Measurements, Recurring [Member] | Investments [Member] | Corporate Equity Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		37,465	33,788	[2]
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		28,165	35,595
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		3,140	5,326
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		1,429	2,744
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		8,888	2,360
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		5,393	16,713
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		9,266	8,102
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			155
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Options [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		4	44
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Futures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		45	29
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Forwards [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			16
Fair Value, Measurements, Recurring [Member] | Financial Derivatives - Assets [Member] | Warrant [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			106
Fair Value, Measurements, Recurring [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value repurchase agreements		155,949	184,819
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments, financial derivatives–assets, and repurchase agreements, at fair value		48	4,467
Total investments sold short, financial derivatives–liabilities, and other secured borrowings, at fair value		(37,199)	(8,223)
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Other secured borrowings [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other secured borrowings, at fair value		0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(36,691)	(8,154)
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments Sold Short [Member] | Agency residential mortgage-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments Sold Short [Member] | Government debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments Sold Short [Member] | Corporate Debt Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments Sold Short [Member] | Common Stock Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(36,691)	(8,154)
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(508)	(69)
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member] | Futures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(508)	(69)
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member] | Forwards [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Liabilities [Member] | Mortgage Loan Purchase Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents		26,500	90,000
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	4,396
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Agency residential mortgage-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | US Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Private Label Residential Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Private Label Commercial Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Commercial Mortgage Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Residential Mortgage Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Collateralized Loan Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Consumer loans and asset-backed securities backed by consumer loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0	[2]
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Corporate Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Investments [Member] | Corporate Equity Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	4,396	[2]
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		48	71
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Options [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		3	42
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Futures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		45	29
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Forwards [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Financial Derivatives - Assets [Member] | Warrant [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value repurchase agreements		0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments, financial derivatives–assets, and repurchase agreements, at fair value		1,594,185	1,197,136
Total investments sold short, financial derivatives–liabilities, and other secured borrowings, at fair value		(641,314)	(594,855)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Other secured borrowings [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other secured borrowings, at fair value		0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(605,549)	(576,742)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments Sold Short [Member] | Agency residential mortgage-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(460,189)	(404,728)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments Sold Short [Member] | Government debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(90,149)	(132,442)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments Sold Short [Member] | Corporate Debt Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		(55,211)	(39,572)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments Sold Short [Member] | Common Stock Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(35,765)	(18,113)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(12,367)	(2,840)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(15,930)	(6,654)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(980)	(2,899)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(6,015)	(5,162)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			(55)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member] | Futures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member] | Forwards [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		(473)	(472)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Liabilities [Member] | Mortgage Loan Purchase Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			(31)
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents		0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		1,413,259	982,380
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Agency residential mortgage-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		989,341	868,345
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | US Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-			5,419
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Private Label Residential Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		158,369	53,525
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Private Label Commercial Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		28,398	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Commercial Mortgage Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Residential Mortgage Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Collateralized Loan Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		185,905	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Consumer loans and asset-backed securities backed by consumer loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0	[2]
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Corporate Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		51,246	55,091
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Investments [Member] | Corporate Equity Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		0	0	[2]
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		24,977	29,937
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		1,429	2,744
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		8,888	2,360
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		5,393	16,713
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		9,266	8,102
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Options [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		1	2
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Futures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Forwards [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			16
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Financial Derivatives - Assets [Member] | Warrant [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value repurchase agreements		155,949	184,819
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments, financial derivatives–assets, and repurchase agreements, at fair value		661,588	523,837
Total investments sold short, financial derivatives–liabilities, and other secured borrowings, at fair value		(125,105)	(505)
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Other secured borrowings [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other secured borrowings, at fair value		(125,105)
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments Sold Short [Member] | Agency residential mortgage-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments Sold Short [Member] | Government debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments Sold Short [Member] | Corporate Debt Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments Sold Short [Member] | Common Stock Sold Short [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments sold short, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	(505)
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			(256)
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			(249)
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member] | Futures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member] | Forwards [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Liabilities [Member] | Mortgage Loan Purchase Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–liabilities, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash Equivalents		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		658,448	518,250
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Agency residential mortgage-backed securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		6,173	29,622
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | US Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Private Label Residential Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		101,297	90,083
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Private Label Commercial Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		12,347	43,268
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Commercial Mortgage Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		108,301	61,129
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Residential Mortgage Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		182,472	84,290
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Collateralized Loan Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		24,911	44,956
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Consumer loans and asset-backed securities backed by consumer loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		135,258	107,157	[2]
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Corporate Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		23,947	25,004
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		26,277	3,349
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Investments [Member] | Corporate Equity Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, at fair value-		37,465	29,392	[2]
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		3,140	5,587
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		3,140	5,326
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			155
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Options [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Futures [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-		0	0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Forwards [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			0
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Financial Derivatives - Assets [Member] | Warrant [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial derivatives–assets, at fair value-			106
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | Repurchase Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value repurchase agreements		$ 0	$ 0

[1] In the Company's Consolidated Statement of Assets, Liabilities, and Equity, all balances associated with repurchase agreements, reverse repurchase agreements, and financial derivatives are presented on a gross basis.

[2] Conformed to current period presentation.