Other Assets (Capital Contributions Made to Loan Origination Partners) (Details) - Loan Originators - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Other Assets [Line Items]
Equity method investments	$ 49,200,000
Impairment on investment	0	$ 58,100,000
Company’s residential whole loans at carrying value are serviced by entities the Company has an investment in	685,800,000
Preferred Stock
Other Assets [Line Items]
Equity method investments	$ 100,800,000

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant