Financing Agreements - Borrowings Under Repurchase Agreement And Associated Assets Pledged as Collateral (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 9,710,754	$ 8,057,175
Mark-to-market financing agreements secured by residential whole loans \| Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	1,544,086	1,814,780
Mark-to-market financing agreements secured by residential whole loans \| Held at Fair Value
Repurchase Agreements
Carrying Value	1,712,489	2,095,002
Fair value of securities pledged against the repurchase agreements	$ 2,204,239	$ 2,632,489
Weighted average haircut (percent)	20.90%	18.33%
Mark-to-market financing agreements secured by securities at fair value \| Held at Fair Value
Repurchase Agreements
Carrying Value	$ 622,603	$ 111,651
Fair value of securities pledged against the repurchase agreements	$ 689,818	$ 177,111
Weighted average haircut (percent)	8.07%	37.43%
Mark-to-market financing agreements secured by real estate owned \| Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 76,629	$ 84,813
Mark-to-market financing agreements secured by real estate owned \| Held at Fair Value
Repurchase Agreements
Carrying Value	25,163	16,394
Fair value of securities pledged against the repurchase agreements	$ 50,365	$ 33,367
Weighted average haircut (percent)	49.39%	48.07%
Non-mark-to-market financing secured by residential whole loans \| Held at Fair Value
Repurchase Agreements
Carrying Value	$ 1,216,697	$ 994,494
Weighted average haircut (percent)	17.65%	21.43%
Non-mark-to-market financing secured by residential whole loans \| Held at Fair Value \| Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 1,510,146	$ 1,301,685
Non-mark-to-market financing secured by real estate owned \| Held at Fair Value
Repurchase Agreements
Carrying Value	$ 0	$ 9,109
Weighted average haircut (percent)	0.00%	60.23%
Non-mark-to-market financing secured by real estate owned \| Held at Fair Value \| Asset Pledged as Collateral with Right
Repurchase Agreements
Fair value of securities pledged against the repurchase agreements	$ 0	$ 22,902

The weighted average percentage amount by which the collateral value is contractually required to exceed the loan amount on the Company's repurchase agreements borrowings.

No definition available.

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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

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-Topic 235
-SubTopic 10
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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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Fair value of securities pledged as collateral against securities sold under agreement to repurchase.

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