Derivative Instruments - Derivative Instruments Effects on Operating Results (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Net unrealized gains (losses) on derivatives	$ 0	$ 0	$ 0	$ 201,000
Net gains (losses) on derivatives	0	0	0	(304,052)
Realized loss on terminations of interest rate swaps	$ 0	$ 0	0	463,966
Interest Rate Swaps
Derivative Instruments, Gain (Loss) [Line Items]
Net unrealized gains (losses) on derivatives			0	204,611
Net realized gains (losses) on derivatives			0	(470,352)
Treasury Futures
Derivative Instruments, Gain (Loss) [Line Items]
Net unrealized gains (losses) on derivatives			0	(3,611)
Net realized gains (losses) on derivatives			0	(34,700)
Swaptions
Derivative Instruments, Gain (Loss) [Line Items]
Net unrealized gains (losses) on derivatives			0	0
Net realized gains (losses) on derivatives			$ 0	$ 0

The net gain (loss) recognized in the statement of operations upon termination of interest rate swap agreements.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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=125515794&loc=SL5618551-113959

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- Definition

The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

+ 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=123570139&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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- Definition

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

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