Commercial Mortgage Loans, Subordinate Loans and Other Lending Assets, Net - Current Expected Credit Losses (Details) - USD ($) $ in Thousands |
Sep. 30, 2022 |
Jun. 30, 2022 |
Mar. 31, 2022 |
Dec. 31, 2021 |
Sep. 30, 2021 |
Jun. 30, 2021 |
Mar. 31, 2021 |
Dec. 31, 2020 |
|---|---|---|---|---|---|---|---|---|
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||||
| Allowance reserve | $ 21,985 | $ 33,588 | ||||||
| Unfunded commitments | 2,812 | $ 3,999 | $ 3,928 | 3,106 | $ 2,193 | $ 2,444 | $ 3,794 | $ 3,365 |
| Total General CECL Allowance | 24,797 | $ 27,361 | $ 25,305 | 36,694 | $ 34,877 | $ 40,643 | $ 40,229 | $ 41,467 |
| Commercial Mortgage Portfolio Segment | ||||||||
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||||
| Allowance reserve | 18,554 | 22,554 | ||||||
| Subordinate Mortgage Portfolio Segment | ||||||||
| Financing Receivable, Allowance for Credit Loss [Line Items] | ||||||||
| Allowance reserve | $ 3,431 | $ 11,034 |