Fair Value of Financial Instruments - Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Carrying Value
Financial Liabilities:
Repurchase agreements	$ 6,987,834	$ 7,228,699
Total	6,987,834	7,228,699
Estimated Fair Value
Financial Liabilities:
Repurchase agreements	6,987,806	7,228,719
Total	$ 6,987,806	$ 7,228,719

Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant