Quarterly report pursuant to Section 13 or 15(d)

Fair Value - Summary of Commercial Mortgage Portfolio Lending (Detail)

v3.22.1
Fair Value - Summary of Commercial Mortgage Portfolio Lending (Detail) - Commercial Mortgage Portfolio Lending [Member]
3 Months Ended 12 Months Ended
Mar. 31, 2022
Dec. 31, 2021
Minimum [Member] | Prepayment Rate [Member]    
Fair Value Portfolio Mortgage Loans Classified Under Mortgage Loans Held For Sale Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Prepayment rate (CPR) 0.00% 0.00%
Minimum [Member] | Default Rate [Member]    
Fair Value Portfolio Mortgage Loans Classified Under Mortgage Loans Held For Sale Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Default rate (CDR)   1.00%
Maximum [Member] | Prepayment Rate [Member]    
Fair Value Portfolio Mortgage Loans Classified Under Mortgage Loans Held For Sale Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Prepayment rate (CPR) 22.60% 14.50%
Maximum [Member] | Default Rate [Member]    
Fair Value Portfolio Mortgage Loans Classified Under Mortgage Loans Held For Sale Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Default rate (CDR)   54.00%
Weighted Average [Member] | Prepayment Rate [Member]    
Fair Value Portfolio Mortgage Loans Classified Under Mortgage Loans Held For Sale Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Prepayment rate (CPR) 13.00% 8.70%
Weighted Average [Member] | Measurement Input, Discount Rate [Member]    
Fair Value Portfolio Mortgage Loans Classified Under Mortgage Loans Held For Sale Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Discount rate 4.90% 3.90%
Weighted Average [Member] | Default Rate [Member]    
Fair Value Portfolio Mortgage Loans Classified Under Mortgage Loans Held For Sale Measured On Recurring And Nonrecurring Basis Fair Value Measurement [Line Items]    
Default rate (CDR) 1.00% 3.20%