Residential Loans - Quarterly Activity of Residential Loans Held-for-Sale (Details) - Residential Loans - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Principal balance of loans acquired	$ 172,162	$ 1,446,750	$ 2,859,813	$ 3,936,111
Principal balance of loans sold	87,868	1,534,315	5,024,663	3,921,280
Net market valuation gains (losses) recorded	$ (478)	$ (6,623)	$ (15,972)	$ 286

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612

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