Derivative Instruments - Net Realized and Unrealized Losses on Derivatives (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized (Gain)/Loss	$ 4,836	$ 1,066
Realized (Gain)/Loss	6,669	1,458
Credit default swaps
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized (Gain)/Loss	(1,752)	112
Realized (Gain)/Loss	61	1,378
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized (Gain)/Loss	4,340	1,197
Realized (Gain)/Loss	2,946	(415)
Treasury note futures
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized (Gain)/Loss	2,248	(243)
Realized (Gain)/Loss	3,627	350
Options
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized (Gain)/Loss	0
Realized (Gain)/Loss	$ 35	$ 145

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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