Loans Subject to Repurchase from Ginnie Mae (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans subject to repurchase from Ginnie Mae	$ 1,175	$ 1,496
Financial Asset, Equal to or Greater than 90 Days Past Due \| Payment Deferral
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans subject to repurchase from Ginnie Mae	$ 1,003	$ 1,301

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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