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Other Assets (Capital Contributions Made to Loan Origination Partners) (Details) - Loan Originators - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Other Assets [Line Items] |  |  |  |
Equity method investments | $ 49,700,000 |  | $ 49,700,000 |
Impairment on investment | 0 | $ 7,100,000 | 0 | $ 65,200,000
Company’s residential whole loans at carrying value are serviced by entities the Company has an investment in | 704,000,000.0 |  | 704,000,000.0 |
Preferred Stock |  |  |  |
Other Assets [Line Items] |  |  |  |
Equity method investments | $ 100,400,000 |  | $ 100,400,000 |

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