Mortgage Loans Held for Sale and Investment - Accretable Yield (Details) - Mortgage Loans Held for Investment $ in Millions	Dec. 31, 2018 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-accrual, UPB	$ 27
Non-accrual, Fair Value	$ 13

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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