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v3.21.2

LOANS - Narrative (Details) | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) | Sep. 30, 2020 USD ($) | Dec. 31, 2020 USD ($) loan | Jan. 01, 2020 USD ($) | Dec. 31, 2019 USD ($)
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Assets | $ 76,662,433,000 |  | $ 76,662,433,000 |  | $ 88,455,103,000 | [1] |  |
Loan loss (provision) reversal | 6,134,000 | $ 21,993,000 | 145,260,000 | $ (146,084,000) |  |  |  |
Allowance for loan loss | 27,700,000 |  | $ 27,700,000 |  | 169,500,000 |  |  |
Minimum |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Senior secured loans, stated maturity (in years) |  |  | 5 years |  |  |  |  |
Maximum |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Senior secured loans, stated maturity (in years) |  |  | 8 years |  |  |  |  |
Cumulative effect of change in accounting principle for credit losses |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Allowance for loan loss |  |  |  |  |  |  |  | $ 37,400,000
Residential Mortgage Loans |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Assets | 1,700,000,000 |  | $ 1,700,000,000 |  | 345,800,000 |  |  |
Loans held-for-sale | $ 3,700,000 |  | $ 3,700,000 |  | $ 47,000,000 |  |  |
Percent of adjustable-rate loans | 22.00% |  | 22.00% |  | 37.00% |  |  |
Commercial Mortgage Loans |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Loan loss (provision) reversal |  | 0 |  | (74,100,000) |  |  |  |
Current period (allowance) reversal |  |  | $ 67,400,000 |  |  |  |  |
Number of loans restructured | loan |  |  |  |  | 5 |  |  |
Restructuring, carrying value |  |  |  |  | $ 243,800,000 |  |  |
Number of contracts modified, partial paydowns | loan |  |  |  |  | 2 |  |  |
Restructuring, partial paydowns |  |  |  |  | $ 4,500,000 |  |  |
Future funding commitments |  |  |  |  | 4,100,000 |  |  |
Loans on nonaccrual status |  |  |  |  | 46,800,000 |  |  |
Interest income, nonaccrual |  |  |  |  | 2,100,000 |  |  |
Unfunded commitments |  |  |  |  | 99,300,000 |  |  |
Unfunded commitments, expected credit loss |  |  |  |  | $ 5,100,000 |  |  |
Loans receivable with variable interest rates |  |  |  |  | 94.00% |  |  |
Commercial Mortgage Loans | Extended Maturity |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Allowance for loan loss |  |  |  |  | $ 23,600,000 |  |  |
Number of loans restructured | loan |  |  |  |  | 4 |  |  |
Commercial Mortgage Loans | Payment Deferral, Forbearance |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Number of loans restructured | loan |  |  |  |  | 1 |  |  |
Forbearance duration |  |  |  |  | 120 days |  |  |
Commercial Mortgage Loans | Cumulative effect, period of adoption, adjusted balance |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Loan loss (provision) reversal |  | 4,900,000 |  | (57,400,000) |  |  |  |
Current period (allowance) reversal |  |  | 62,500,000 |  |  |  |  |
Commercial Mortgage Loans | Cumulative effect of change in accounting principle for credit losses |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Allowance for loan loss |  |  |  |  |  |  | $ 7,800,000 |
Corporate Loans |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Loan loss (provision) reversal |  | 5,400,000 | 0 | (4,500,000) |  |  |  |
Loans held-for-sale | $ 2,100,000 |  | 2,100,000 |  | $ 0 |  |  |
Unfunded commitments | 221,700,000 |  | 221,700,000 |  | 87,300,000 |  |  |
Unfunded commitments, expected credit loss | 500,000 |  | 500,000 |  | 700,000 |  |  |
Principal balance |  | 9,700,000 |  | 29,300,000 |  |  |  |
Carrying value |  | 9,600,000 |  | 21,900,000 |  |  |  |
Debt |  | 4,800,000 |  | 4,800,000 |  |  |  |
Allowance for loan losses, writeoffs |  |  |  | 11,900,000 |  |  |  |
Corporate Loans | Second lien loans |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Debt |  | 2,800,000 |  | 2,800,000 |  |  |  |
Corporate Loans | First lien loans |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Allowance for loan losses, writeoffs |  |  |  | 19,600,000 |  |  |  |
Corporate Loans | Cumulative effect, period of adoption, adjusted balance |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Loan loss (provision) reversal | 6,100,000 | $ 11,600,000 | 11,800,000 | $ (10,100,000) |  |  |  |
Corporate Loans | Cumulative effect of change in accounting principle for credit losses |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Allowance for loan loss |  |  |  |  |  |  | $ 29,700,000 |
Residential mortgage loan warehouse facility |  |  |  |  |  |  |  |
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] |  |  |  |  |  |  |  |
Assets | $ 1,431,000 |  | $ 1,431,000 |  | $ 0 |  |  |
[1] | (1)Derived from the audited consolidated financial statements at December 31, 2020.

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