Secured Financing Agreements - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Repurchase Agreement Counterparty [Line Items]
Repurchase agreements outstanding	$ 2,820,931	$ 3,261,613
Margin cash collateral pledged to repurchase agreement counterparties	$ 55,642	19,078
Decrease in share price (as a percent)	50.00%
Warehouse Agreement Borrowings
Repurchase Agreement Counterparty [Line Items]
Unused warehouse credit facilities	$ 2,000,000
Minimum \| Warehouse Agreement Borrowings
Repurchase Agreement Counterparty [Line Items]
Maturity dates of credit facility	30 days
Maximum \| Warehouse Agreement Borrowings
Repurchase Agreement Counterparty [Line Items]
Maturity dates of credit facility	1 year
Not Subject to Additional Margin Requirements Upon Change in Fair Value of Collateral Pledged
Repurchase Agreement Counterparty [Line Items]
Repurchase agreements outstanding	$ 737,000	1,200,000
Not Subject to Additional Margin Requirements Until Drop in Fair Value of Collateral
Repurchase Agreement Counterparty [Line Items]
Repurchase agreements outstanding	$ 476,000	$ 113,000

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ References

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+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against securities sold under agreement to repurchase.

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