Fair Value Measurements - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Mortgage Loans Held for Investment \| Fair Value, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Transfers from mortgage loans held for investment to held for sale	$ (12)

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.

No definition available.

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