Quarterly report pursuant to Section 13 or 15(d)

Fair Value - Summary of Commercial Mortgage Loans (Details)

v3.21.2
Fair Value - Summary of Commercial Mortgage Loans (Details) - Commercial Mortgage Loans [Member]
 9 Months Ended 12 Months Ended
Sep. 30, 2021
Dec. 31, 2020
Maximum [Member] | Weighted average remaining life in months [Member]    
Fair Value Non Recourse Debt Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Weighted-average remaining life (in months)   4 months 3 days
Maximum [Member] | Weighted-average prepayment speed (SMM) [Member]    
Fair Value Non Recourse Debt Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Weighted-average prepayment speed (SMM)   32.00%
Minimum [Member] | Weighted average remaining life in months [Member]    
Fair Value Non Recourse Debt Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Weighted-average remaining life (in months)   1 month 27 days
Minimum [Member] | Weighted-average prepayment speed (SMM) [Member]    
Fair Value Non Recourse Debt Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Weighted-average prepayment speed (SMM)   17.70%
Weighted Average [Member] | Weighted average remaining life in months [Member]    
Fair Value Non Recourse Debt Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Weighted-average remaining life (in months) 4 months 3 months 12 days
Weighted Average [Member] | Weighted-average prepayment speed (SMM) [Member]    
Fair Value Non Recourse Debt Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Weighted-average prepayment speed (SMM) 14.00% 21.40%
Weighted Average [Member] | Discount rate [Member]    
Fair Value Non Recourse Debt Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Discount rate 2.60% 5.80%