Commitments and Contingencies (Residential Whole Loan Purchase Commitments) (Details) $ in Millions	Dec. 31, 2018 USD ($)
Other Commitments [Line Items]
Excluded amount, unsettled purchases, residential whole loans, at fair value	$ 194.7
Residential whole loans
Other Commitments [Line Items]
Excluded amount, unsettled purchases, residential whole loans, at fair value	$ 194.7

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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