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Other Assets - Impact of Derivative Instruments on Earnings (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Derivative [Line Items]
Income on swap variable receive leg	$ 33,851	$ 408
Expense on swap fixed pay leg	(12,034)	(5,936)
Net price alignment expense on margin collateral received	(2,278)	0
Net gain on TBA short positions	0	18,876
Total Net (loss)/gain on derivatives used for risk management purposes	(21,208)	94,101
Agreements with mark-to-market collateral provisions
Derivative [Line Items]
Unrealized mark-to-market (loss)/gain	$ (40,747)	$ 80,753

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- Definition

Derivatives Income on SWAP Variable Receive Leg

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- Definition

Derivatives Price Alignment Expense on Margin Collateral Received

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- Definition

Expense on swap Fixed Pay Leg

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- References

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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.

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No definition available.

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- Definition

Gain (loss) incurred in risk management activities.

+ 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 https://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959

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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

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 https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

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