Investment in Loans Investment in Loans (Schedule of Residential Mortgage Loans: Performance) (Details) - USD ($) $ in Thousands |
Mar. 31, 2020 |
Dec. 31, 2019 |
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|---|---|---|---|---|
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||
| Unpaid Principal Balance | $ 1,441,017 | $ 1,387,733 | ||
| Loans, at fair value | [1] | 1,443,589 | 1,412,426 | |
| Residential mortgage loans | ||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||
| Unpaid Principal Balance | 940,480 | 911,705 | ||
| Loans, at fair value | 939,372 | 932,203 | ||
| Residential mortgage loans | Performing Financial Instruments [Member] | ||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||
| Unpaid Principal Balance | 29,235 | 27,663 | ||
| Loans, at fair value | 25,065 | 25,323 | ||
| Residential mortgage loans | Non-performing | ||||
| Accounts, Notes, Loans and Financing Receivable [Line Items] | ||||
| Unpaid Principal Balance | 17,052 | 17,757 | ||
| Loans, at fair value | $ 14,839 | $ 15,580 | ||
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