Consolidated Condensed Schedule Of Investments (Financial Derivatives)		6 Months Ended		12 Months Ended
		Jun. 30, 2016 USD ($) contracts		Dec. 31, 2015 USD ($) contracts
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[1]	$ 152,628,000		$ 162,905,000
Derivative Liabilities	[1]	(74,098,000)		(60,472,000)
Net cost		149,985,000		163,943,000
Net proceeds		(43,032,000)		(56,200,000)
Eurodollar Future [Member]
Investment Holdings, Other than Securities [Line Items]
Future contract notional		$ 1,000,000		$ 1,000,000
Future contract | contracts		1		1
Financial Derivatives - Assets [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 152,628,000	[2]	$ 162,905,000	[3]
Financial Derivative Assets, Percent of Net Assets		22.47%	[2],[4]	22.05%	[3],[5]
Net cost		$ 149,985,000	[2]	$ 163,934,000	[3]
Financial Derivatives - Assets [Member] | Affiliates of Bank of America [Member]
Investment Holdings, Other than Securities [Line Items]
Financial Derivative Assets, Percent of Net Assets		7.25%		6.01%
Financial Derivatives - Assets [Member] | Affiliates of JP Morgan [Member]
Investment Holdings, Other than Securities [Line Items]
Financial Derivative Assets, Percent of Net Assets		5.57%
Financial Derivatives - Assets [Member] | Swap [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 150,933,000	[2],[6]	$ 159,423,000	[3],[7]
Financial Derivative Assets, Percent of Net Assets		22.22%	[2],[4],[6]	21.58%	[3],[5],[7]
Net cost		$ 149,884,000	[2],[6]	$ 161,193,000	[3],[7]
Financial Derivatives - Assets [Member] | Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 8,000	[2]	$ 32,000	[3]
Financial Derivative Assets, Percent of Net Assets		0.00%	[2],[4]	0.01%	[3],[5]
Financial Derivatives - Assets [Member] | Options [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 1,000	[2]	$ 2,162,000	[3]
Financial Derivative Assets, Percent of Net Assets		0.00%	[2],[4]	0.29%	[3],[5]
Net cost		$ 1,000	[2]	$ 2,600,000	[3]
Financial Derivatives - Assets [Member] | Forwards [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 1,578,000	[2]	$ 1,138,000	[3]
Financial Derivative Assets, Percent of Net Assets		0.23%	[2],[4]	0.15%	[3],[5]
Financial Derivatives - Assets [Member] | Warrant [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 100,000	[2]	$ 150,000	[3]
Financial Derivative Assets, Percent of Net Assets		0.02%	[2],[4]	0.02%	[3],[5]
Net cost		$ 100,000	[2]	$ 150,000	[3]
Financial Derivatives - Assets [Member] | Mortgage Loan Purchase Commitments [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2]	$ 8,000
Financial Derivative Assets, Percent of Net Assets	[2],[4]	0.00%
Financial Derivatives - Liabilities [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (74,098,000)	[2]	$ (60,472,000)	[3]
Financial Derivative Liabilities, Percent of Net Assets		(10.91%)	[2],[4]	(8.18%)	[3],[5]
Net proceeds		$ (43,032,000)	[2]	$ (56,200,000)	[3]
Financial Derivatives - Liabilities [Member] | Affiliates of JP Morgan [Member]
Investment Holdings, Other than Securities [Line Items]
Financial Derivative Liabilities, Percent of Net Assets		(7.42%)		(6.32%)
Financial Derivatives - Liabilities [Member] | Swap [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (73,497,000)	[2],[6]	$ (58,163,000)	[3],[7]
Financial Derivative Liabilities, Percent of Net Assets		(10.82%)	[2],[4],[6]	(7.87%)	[3],[5],[7]
Net proceeds		$ (42,107,000)	[2],[6]	$ (53,679,000)	[3],[7]
Financial Derivatives - Liabilities [Member] | Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (358,000)	[2]	$ (528,000)	[3]
Financial Derivative Liabilities, Percent of Net Assets		(0.05%)	[2],[4]	(0.07%)	[3],[5]
Financial Derivatives - Liabilities [Member] | Options [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (243,000)	[2]	$ (1,760,000)	[3]
Financial Derivative Liabilities, Percent of Net Assets		(0.04%)	[2],[4]	(0.24%)	[3],[5]
Net proceeds		$ (925,000)	[2]	$ (2,521,000)	[3]
Financial Derivatives - Liabilities [Member] | Forwards [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3]			$ (13,000)
Financial Derivative Liabilities, Percent of Net Assets	[3],[5]			0.00%
Financial Derivatives - Liabilities [Member] | Mortgage Loan Purchase Commitments [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3]			$ (8,000)
Financial Derivative Liabilities, Percent of Net Assets	[3],[5]			0.00%
Put Option [Member] | Options on U.S. Treasury Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Number of contracts | contracts				39
Call Option [Member] | Options on U.S. Treasury Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Number of contracts | contracts				39
Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Mortgage Loan Purchase Commitments [Member] | Mortgage-related Residential [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[8]	8,000
Derivative Asset, Notional Amount	[2],[8]	$ 2,330,000
Range of expiration dates	[2],[8]	2016-07
Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Mortgage Loan Purchase Commitments [Member] | Mortgage-related Residential [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[9]			$ (8,000)
Derivative Liability, Notional Amount	[3],[9]			$ 7,713,000
Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Mortgage Loan Purchase Commitments [Member] | Mortgage-related Residential [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[9]			2016-01
Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Mortgage Loan Purchase Commitments [Member] | Mortgage-related Residential [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[9]			2016-02
Equity Market Risk [Member] | Financial Derivatives - Assets [Member] | Warrant [Member] | North America [Member] | Mortgage-related Residential [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 100,000	[2],[10]	$ 150,000	[3],[11]
Derivative Asset, Notional Amount		$ 1,554,000	[2],[10]	$ 1,555,000	[3],[11]
Long [Member] | US Treasury Note Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Number of contracts | contracts		16		343
Long [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[6],[12]	$ 100,887,000
Long [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		824,000	[2],[6],[13]	$ 85,000	[3],[7]
Long [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[6],[12]	122,000
Long [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		(1,016,000)	[2],[6]	(4,662,000)	[3],[7]
Long [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[2],[6],[12]	(1,879,000)
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[3],[7],[14]			135,752,000
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		51,000	[2],[6],[12]	56,000	[3],[7],[14]
Derivative Asset, Notional Amount		$ 1,340,000	[2],[6],[12]	$ 1,468,000	[3],[7],[14]
Range of expiration dates		2037-12	[2],[6],[12]	2037-12	[3],[7],[14]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Communications [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 89,000	[2],[6],[13]	$ 49,000	[3],[7],[15]
Derivative Asset, Notional Amount		$ 6,733,000	[2],[6],[13]	$ 3,836,000	[3],[7],[15]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Communications [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2017-02	[2],[6],[13]	2016-03	[3],[7],[15]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Communications [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2017-04	[2],[6],[13]	2016-12	[3],[7],[15]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Consumer [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 199,000	[2],[6],[13]	$ 31,000	[3],[7],[15]
Derivative Asset, Notional Amount		$ 3,465,000	[2],[6],[13]	$ 4,880,000	[3],[7],[15]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Consumer [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2017-02	[2],[6],[13]	2016-03	[3],[7],[15]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Consumer [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2017-03	[2],[6],[13]	2017-01	[3],[7],[15]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Energy [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[3],[7],[15]			$ 5,000
Derivative Asset, Notional Amount	[3],[7],[15]			$ 729,000
Range of expiration dates	[3],[7],[15]			2016-10
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Industrial [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[6],[13]	$ 357,000
Derivative Asset, Notional Amount	[2],[6],[13]	$ 3,710,000
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Industrial [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[13]	2017-02
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Industrial [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[13]	2017-03
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Total Return Swaps [Member] | North America [Member] | Utilities [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[6],[13]	$ 179,000
Derivative Asset, Notional Amount	[2],[6],[13]	$ 2,330,000
Range of expiration dates	[2],[6],[13]	2017-02
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Communications [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[6],[12]	$ 71,000
Derivative Asset, Notional Amount	[2],[6],[12]	$ 1,300,000
Range of expiration dates	[2],[6],[12]	2021-06
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Consumer [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[6],[12]	$ 34,000
Derivative Asset, Notional Amount	[2],[6],[12]	$ 1,535,000
Range of expiration dates	[2],[6],[12]	2021-06
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Industrial [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[6],[12]	$ 17,000
Derivative Asset, Notional Amount	[2],[6],[12]	$ 1,463,000
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Industrial [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[12]	2020-12
Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Industrial [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[12]	2021-06
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (5,868,000)	[2],[6],[12]	$ (365,000)	[3],[7],[14]
Derivative Liability, Notional Amount		$ 31,413,000	[2],[6],[12]	$ 4,458,000	[3],[7],[14]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Indices [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2047-01	[2],[6],[12]	2052-10	[3],[7],[14]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Indices [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2058-09	[2],[6],[12]	2063-05	[3],[7],[14]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Basic Materials [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (320,000)	[2],[6],[13]	$ (822,000)	[3],[7],[15]
Derivative Liability, Notional Amount		$ 6,638,000	[2],[6],[13]	$ 6,477,000	[3],[7],[15]
Range of expiration dates	[3],[7],[15]			2016-03
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Basic Materials [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[13]	2017-02
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Basic Materials [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[13]	2017-03
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Communications [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (260,000)	[2],[6],[13]	$ (2,581,000)	[3],[7],[15]
Derivative Liability, Notional Amount		$ 2,295,000	[2],[6],[13]	$ 11,009,000	[3],[7],[15]
Range of expiration dates	[2],[6],[13]	2017-02
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Communications [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[7],[15]			2016-03
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Communications [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[7],[15]			2016-08
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Consumer [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (434,000)	[2],[6],[13]	$ (143,000)	[3],[7],[15]
Derivative Liability, Notional Amount		$ 2,104,000	[2],[6],[13]	$ 4,983,000	[3],[7],[15]
Range of expiration dates	[2],[6],[13]	2017-02
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Consumer [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[7],[15]			2016-06
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Consumer [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[7],[15]			2016-08
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Diversified [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[7],[15]			$ (171,000)
Derivative Liability, Notional Amount	[3],[7],[15]			$ 2,765,000
Range of expiration dates	[3],[7],[15]			2016-03
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Energy [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[7],[15]			$ (812,000)
Derivative Liability, Notional Amount	[3],[7],[15]			$ 4,076,000
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Energy [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[7],[15]			2016-04
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Energy [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[7],[15]			2016-08
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Financial [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (2,000)	[2],[6],[13]	$ (10,000)	[3],[7],[15]
Derivative Liability, Notional Amount		$ 2,086,000	[2],[6],[13]	$ 2,646,000	[3],[7],[15]
Range of expiration dates		2017-02	[2],[6],[13]	2016-09	[3],[7],[15]
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Industrial [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[7],[15]			$ (39,000)
Derivative Liability, Notional Amount	[3],[7],[15]			$ 1,000,000
Range of expiration dates	[3],[7],[15]			2016-03
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Technology [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[7],[15]			$ (84,000)
Derivative Liability, Notional Amount	[3],[7],[15]			$ 2,650,000
Range of expiration dates	[3],[7],[15]			2017-01
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Basic Materials [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[2],[6],[12]	$ (492,000)
Derivative Liability, Notional Amount	[2],[6],[12]	$ 2,700,000
Range of expiration dates	[2],[6],[12]	2021-06
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Energy [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[2],[6],[12]	$ (1,387,000)
Derivative Liability, Notional Amount	[2],[6],[12]	$ 5,447,000
Range of expiration dates	[2],[6],[12]	2021-06
Long [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | Europe [Member] | Basic Materials [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[2],[6],[12]	$ (6,000)
Derivative Liability, Notional Amount	[2],[6],[12]	$ 12,000
Range of expiration dates	[2],[6],[12]	2019-12
Long [Member] | Credit Risk [Member] | Put Option [Member] | Financial Derivatives - Assets [Member] | Options on Credit Default Swaps on Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[3],[16]			$ 2,050,000
Derivative Asset, Notional Amount	[3],[16]			$ 138,000,000
Range of expiration dates	[3],[16]			2016-03
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 13,931,000	[2],[6],[17]	$ 7,254,000	[3],[7],[18]
Derivative Asset, Notional Amount		$ 524,260,000	[2],[6],[17]	$ 545,232,000	[3],[7],[18]
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2016-12	[2],[6],[17]	2016-12	[3],[7],[18]
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2046-06	[2],[6],[17]	2045-12	[3],[7],[18]
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | US Treasury Note Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 2,000	[2],[19]	$ 2,000	[3],[20]
Derivative Asset, Notional Amount		$ 2,000,000	[2],[19]	$ 6,300,000	[3],[20]
Range of expiration dates		2016-09	[2],[19]	2016-03	[3],[20]
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Eurodollar Future [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 4,000	[2],[21]	$ 17,000	[3],[22]
Derivative Asset, Notional Amount		$ 11,000,000	[2],[21]	$ 23,000,000	[3],[22]
Range of expiration dates		2017-06	[2],[21]	2017-06	[3],[22]
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Interest Rate Cap [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[23]	$ 1,000
Derivative Asset, Notional Amount	[2],[23]	$ 23,200,000
Range of expiration dates	[2],[23]	2018-03
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (2,000)	[2],[6],[17]	$ (278,000)	[3],[7],[18]
Derivative Liability, Notional Amount		$ 3,564,000	[2],[6],[17]	$ 129,975,000	[3],[7],[18]
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2016-10	[2],[6],[17]	2016-10	[3],[7],[18]
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2046-07	[2],[6],[17]	2045-12	[3],[7],[18]
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | US Treasury Note Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[20]			$ (235,000)
Derivative Liability, Notional Amount	[3],[20]			$ 37,700,000
Range of expiration dates	[3],[20]			2016-03
Long [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Straddle Swaption [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[24]			$ (31,000)
Derivative Liability, Notional Amount	[3],[24]			$ 8,400,000
Range of expiration dates	[3],[24]			2018-11
Long [Member] | Interest Rate Risk [Member] | Put Option [Member] | Financial Derivatives - Assets [Member] | Options on U.S. Treasury Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[3],[25]			$ 61,000
Derivative Asset, Notional Amount	[3],[25]			$ 3,900,000
Range of expiration dates	[3],[25]			2016-02
Long [Member] | Interest Rate Risk [Member] | Call Option [Member] | Financial Derivatives - Assets [Member] | Options on U.S. Treasury Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[3],[25]			$ 51,000
Derivative Asset, Notional Amount	[3],[25]			$ 3,900,000
Range of expiration dates	[3],[25]			2016-02
Long [Member] | Equity Market Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Energy [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[7],[26]			$ 0
Derivative Liability, Notional Amount	[3],[7],[26]			$ 35,000
Range of expiration dates	[3],[7],[26]			2017-07
Long [Member] | Equity Market Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Financial [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[7],[26]			$ 0
Derivative Liability, Notional Amount	[3],[7],[26]			$ 21,635,000
Range of expiration dates	[3],[7],[26]			2016-11
Long [Member] | Currency risk [Member] | Financial Derivatives - Liabilities [Member] | Forwards [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[27]			$ (13,000)
Derivative Liability, Notional Amount	[3],[27]			$ 2,734,000
Range of expiration dates	[3],[27]			2016-03
Short [Member] | US Treasury Note Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Number of contracts | contracts		16
Short [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[6],[28]	$ 461,000
Short [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[7]			$ 0
Short [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		(1,837,000)	[2],[6],[28]	(683,000)	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		4,024,000	[2],[6],[28]	1,891,000	[3],[7],[29]
Derivative Asset, Notional Amount		$ (63,527,000)	[2],[6],[28]	$ (15,208,000)	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2017-12	[2],[6],[28]	2017-12	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2021-06	[2],[6],[28]	2019-12	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 24,565,000	[2],[6],[28]	$ 5,354,000	[3],[7],[29]
Derivative Asset, Notional Amount		$ (140,273,000)	[2],[6],[28]	$ (95,589,000)	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Indices [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2046-05	[2],[6],[28]	2046-05	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Indices [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2063-05	[2],[6],[28]	2063-05	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Consumer [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[3],[7],[29]			$ 10,000
Derivative Asset, Notional Amount	[3],[7],[29]			$ (590,000)
Range of expiration dates	[3],[7],[29]			2019-12
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Energy [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[6],[28]	$ 461,000
Derivative Asset, Notional Amount	[2],[6],[28]	$ (7,290,000)
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Energy [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[28]	2017-06
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Energy [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[28]	2021-06
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Securities [Member] | North America [Member] | Mortgage-related Residential [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 6,068,000	[2],[6],[28]	$ 6,332,000	[3],[7],[29]
Derivative Asset, Notional Amount		$ (8,213,000)	[2],[6],[28]	$ (8,967,000)	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Securities [Member] | North America [Member] | Mortgage-related Residential [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2035-05	[2],[6],[28]	2034-09	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Asset Backed Securities [Member] | North America [Member] | Mortgage-related Residential [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2035-12	[2],[6],[28]	2035-12	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (39,797,000)	[2],[6],[28]	$ (47,298,000)	[3],[7],[29]
Derivative Liability, Notional Amount		$ (985,654,000)	[2],[6],[28]	$ (1,001,913,000)	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bond Indices [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2016-12	[2],[6],[28]	2016-12	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bond Indices [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2021-06	[2],[6],[28]	2020-12	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Basic Materials [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[2],[6],[28]	$ (1,000)
Derivative Liability, Notional Amount	[2],[6],[28]	$ (2,990,000)
Range of expiration dates	[2],[6],[28]	2017-06
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Communications [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[2],[6],[28]	$ (71,000)
Derivative Liability, Notional Amount	[2],[6],[28]	$ (1,300,000)
Range of expiration dates	[2],[6],[28]	2021-06
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Consumer [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (1,509,000)	[2],[6],[28]	$ (584,000)	[3],[7],[29]
Derivative Liability, Notional Amount		$ (14,580,000)	[2],[6],[28]	$ (8,780,000)	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Consumer [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2018-06	[2],[6],[28]	2019-09	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Consumer [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2021-06	[2],[6],[28]	2020-12	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Technology [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[2],[6],[28]	$ (256,000)
Derivative Liability, Notional Amount	[2],[6],[28]	$ (2,200,000)
Range of expiration dates	[2],[6],[28]	2020-03
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Corporate Bonds [Member] | North America [Member] | Financial [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[7],[29]			$ (99,000)
Derivative Liability, Notional Amount	[3],[7],[29]			$ (4,000,000)
Range of expiration dates	[3],[7],[29]			2020-03
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Securities [Member] | North America [Member] | Mortgage-related Residential [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (234,000)	[2],[6],[28]	$ (221,000)	[3],[7],[29]
Derivative Liability, Notional Amount		$ (3,159,000)	[2],[6],[28]	$ (3,209,000)	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Securities [Member] | North America [Member] | Mortgage-related Residential [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2034-10	[2],[6],[28]	2034-10	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Financial Derivatives - Liabilities [Member] | Credit Default Swaps On Asset Backed Securities [Member] | North America [Member] | Mortgage-related Residential [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2035-03	[2],[6],[28]	2035-03	[3],[7],[29]
Short [Member] | Credit Risk [Member] | Put Option [Member] | Financial Derivatives - Liabilities [Member] | Options on Credit Default Swaps on Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (243,000)	[2],[30]	$ (720,000)	[3],[31]
Derivative Liability, Notional Amount		$ (155,500,000)	[2],[30]	$ (171,750,000)	[3],[31]
Short [Member] | Credit Risk [Member] | Put Option [Member] | Financial Derivatives - Liabilities [Member] | Options on Credit Default Swaps on Corporate Bond Indices [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2016-07	[2],[30]	2016-02	[3],[31]
Short [Member] | Credit Risk [Member] | Put Option [Member] | Financial Derivatives - Liabilities [Member] | Options on Credit Default Swaps on Corporate Bond Indices [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2016-09	[2],[30]	2016-03	[3],[31]
Short [Member] | Credit Risk [Member] | Call Option [Member] | Financial Derivatives - Liabilities [Member] | Options on Credit Default Swaps on Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[32]			$ (884,000)
Derivative Liability, Notional Amount	[3],[32]			$ (273,100,000)
Short [Member] | Credit Risk [Member] | Call Option [Member] | Financial Derivatives - Liabilities [Member] | Options on Credit Default Swaps on Corporate Bond Indices [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[32]			2016-01
Short [Member] | Credit Risk [Member] | Call Option [Member] | Financial Derivatives - Liabilities [Member] | Options on Credit Default Swaps on Corporate Bond Indices [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[32]			2016-02
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[3],[7],[33]			$ 2,689,000
Derivative Asset, Notional Amount	[3],[7],[33]			$ (608,365,000)
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[7],[33]			2016-12
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Interest Rate Swaps [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3],[7],[33]			2045-12
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | US Treasury Note Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[19]	$ 0
Derivative Asset, Notional Amount	[2],[19]	$ (100,000)
Range of expiration dates	[2],[19]	2016-09
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | US Treasury Bond Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[2],[19]	$ 2,000
Derivative Asset, Notional Amount	[2],[19]	$ (100,000)
Range of expiration dates	[2],[19]	2016-09
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Assets [Member] | Eurodollar Future [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[3],[22]			$ 13,000
Derivative Asset, Notional Amount	[3],[22]			$ (90,000,000)
Range of expiration dates	[3],[22]			2016-12
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (22,856,000)	[2],[6],[34]	$ (4,656,000)	[3],[7],[33]
Derivative Liability, Notional Amount		$ (949,730,000)	[2],[6],[34]	$ (518,235,000)	[3],[7],[33]
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2016-09	[2],[6],[34]	2016-01	[3],[7],[33]
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Interest Rate Swaps [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2046-07	[2],[6],[34]	2046-01	[3],[7],[33]
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | US Treasury Note Futures [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[2],[19]	$ (5,000)
Derivative Liability, Notional Amount	[2],[19]	$ (1,400,000)
Range of expiration dates	[2],[19]	2016-09
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Eurodollar Future [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (353,000)	[2],[21]	$ (293,000)	[3],[22]
Derivative Liability, Notional Amount		$ (266,000,000)	[2],[21]	$ (306,000,000)	[3],[22]
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Eurodollar Future [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2016-09	[2],[21]	2016-03	[3],[22]
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Eurodollar Future [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2017-09	[2],[21]	2017-09	[3],[22]
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Straddle Swaption [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[24]			$ (125,000)
Derivative Liability, Notional Amount	[3],[24]			$ (13,100,000)
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Straddle Swaption [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3]			2016-01
Short [Member] | Interest Rate Risk [Member] | Financial Derivatives - Liabilities [Member] | Straddle Swaption [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[3]			2016-06
Short [Member] | Equity Market Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Energy [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities	[3],[7],[26]			$ 0
Derivative Liability, Notional Amount	[3],[7],[26]			$ (58,000)
Range of expiration dates	[3],[7],[26]			2017-07
Short [Member] | Equity Market Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Financial [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Liabilities		$ (2,000)	[2],[6],[35]	$ 0	[3],[7],[26]
Derivative Liability, Notional Amount		$ (78,839,000)	[2],[6],[35]	$ (4,048,000)	[3],[7],[26]
Range of expiration dates	[3],[7],[26]			2017-03
Short [Member] | Equity Market Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Financial [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[35]	2017-02
Short [Member] | Equity Market Risk [Member] | Financial Derivatives - Liabilities [Member] | Total Return Swaps [Member] | North America [Member] | Financial [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates	[2],[6],[35]	2019-10
Short [Member] | Currency risk [Member] | Financial Derivatives - Assets [Member] | Forwards [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 1,578,000	[2],[36]	$ 1,138,000	[3],[37]
Derivative Asset, Notional Amount		$ (74,782,000)	[2],[36]	$ (95,326,000)	[3],[37]
Range of expiration dates		2016-09	[2],[36]	2016-03	[3],[37]
CDX.NA.HY 25 35-100 [Member] | Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 73,594,000	[2],[6],[12]	$ 81,758,000	[3],[7],[14]
Derivative Asset, Notional Amount		$ 399,212,000	[2],[6],[12]	$ 442,140,000	[3],[7],[14]
Range of expiration dates		2020-12	[2],[6],[12]	2020-12	[3],[7],[14]
ITRX EUR XOVER 24 5Y 35-100 [Member] | Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset	[3],[7],[14]			$ 46,716,000
Derivative Asset, Notional Amount	[3],[7],[14]			$ 229,954,000
Range of expiration dates	[3],[7],[14]			2020-12
Other Credit Default Swaps on Corporate Bond Indices [Member] | Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member]
Investment Holdings, Other than Securities [Line Items]
Derivative Asset		$ 27,293,000	[2],[6],[12]	$ 7,278,000	[3],[7],[14]
Derivative Asset, Notional Amount		$ 297,148,000	[2],[6],[12]	$ 121,730,000	[3],[7],[14]
Other Credit Default Swaps on Corporate Bond Indices [Member] | Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member] | Minimum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2018-06	[2],[6],[12]	2018-06	[3],[7],[14]
Other Credit Default Swaps on Corporate Bond Indices [Member] | Long [Member] | Credit Risk [Member] | Financial Derivatives - Assets [Member] | Credit Default Swaps On Corporate Bond Indices [Member] | Maximum [Member]
Investment Holdings, Other than Securities [Line Items]
Range of expiration dates		2021-06	[2],[6],[12]	2020-06	[3],[7],[14]

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

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

[4] Classification percentages are based on Total Equity.

[5] Classification percentages are based on Total Equity.

[6] The following table shows the Company's swap assets and liabilities by dealer as a percentage of Total Equity:Dealer/Parent Company Asset/Liability Percent of EquityAffiliates of Bank of America Financial derivatives—asset 7.25 %Affiliates of JP Morgan Financial derivatives—asset 5.57 %Affiliates of JP Morgan Financial derivatives—liability (7.42)%

[7] The following table shows the Company's swap assets and liabilities by dealer as a percentage of Total Equity:Dealer/Parent Company Asset/Liability Percent of EquityAffiliates of Bank of America Financial derivatives—asset 6.01 %Affiliates of JP Morgan Financial derivatives—liability (6.32)%

[8] Notional value represents principal balance of mortgage loan purchase commitments. Actual loan purchases are contingent upon successful loan closings in accordance with agreed-upon parameters.

[9] Notional value represents principal balance of mortgage loan purchase commitments. Actual loan purchases are contingent upon successful loan closings in accordance with agreed-upon parameters.

[10] Notional value represents number of warrants.

[11] Notional value represents number of warrants.

[12] For long credit default swaps, the Company sold protection.

[13] Notional value represents outstanding principal balance on underlying corporate debt.

[14] For long credit default swaps, the Company sold protection.

[15] Notional value represents outstanding principal balance on underlying corporate debt.

[16] Represents the option on the part of the Company to enter into a credit default swap on a corporate bond index whereby the Company would pay a fixed rate and receive credit protection payments.

[17] For long interest rate swap contracts, the Company pays a floating rate and receives a fixed rate.

[18] For long interest rate swap contracts, the Company pays a floating rate and receives a fixed rate.

[19] Notional value represents the total face amount of U.S. Treasury securities underlying all contracts held; as of June 30, 2016, 16 long contracts and 16 short contracts were held.

[20] Notional value represents the total face amount of U.S. Treasury Notes underlying all contracts held; as of December 31, 2015, 343 long futures contracts were held.

[21] Every $1,000,000 in notional value represents one contract.

[22] Every $1,000,000 in notional value represents one contract.

[23] Notional value represents the amount on which interest payments are calculated to the extent the market interest rate exceeds the rate cap on the contract.

[24] Represents the combination of a written payer swaption and a written receiver swaption on the same underlying swap.

[25] Represents the option on the part of the Company to enter into a futures contract with a counterparty; as of December 31, 2015, 39 put options and 39 call options contracts were held.

[26] Notional value represents number of underlying shares times the closing price of the underlying security.

[27] Notional value represents U.S. Dollars to be paid by the Company at the maturity of the forward contract.

[28] For short credit default swaps, the Company purchased protection.

[29] For short credit default swaps, the Company purchased protection.

[30] Represents the option on the part of a counterparty to enter into a credit default swap on a corporate bond index whereby the Company would receive a fixed rate and pay credit protection payments.

[31] Represents the option on the part of a counterparty to enter into a credit default swap on a corporate bond index whereby the Company would receive a fixed rate and pay credit protection payments.

[32] Represents the option on the part of a counterparty to enter into a credit default swap on a corporate bond index whereby the Company would pay a fixed rate and receive credit protection payments.

[33] For short interest rate swap contracts, the Company pays a fixed rate and receives a floating rate.

[34] For short interest rate swap contracts, the Company pays a fixed rate and receives a floating rate.

[35] Notional value represents number of underlying shares times the closing price of the underlying security.

[36] Notional value represents U.S. Dollars to be received by the Company at the maturity of the forward contract.

[37] Notional value represents U.S. Dollars to be received by the Company at the maturity of the forward contract.