v3.22.0.1
Trading Cash Instruments - Fair Value, Cash Instruments, Measurement Inputs, Disclosure (Detail)
$ in Millions
Dec. 31, 2021
USD ($)
yr
Dec. 31, 2020
USD ($)
yr
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Total financial assets at fair value | $ $ 715,812 $ 627,073
Level 3 [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Total financial assets at fair value | $ 24,083 26,305
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Total financial assets at fair value | $ $ 137 $ 203
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member] | Minimum [Member] | Fair Value Unobservable Inputs, Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.028 0.017
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member] | Minimum [Member] | Fair Value Unobservable Inputs, Recovery Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.051 0.051
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member] | Minimum [Member] | Fair Value Unobservable Inputs, Duration [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.1 1.1
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member] | Maximum [Member] | Fair Value Unobservable Inputs, Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.285 0.220
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member] | Maximum [Member] | Fair Value Unobservable Inputs, Recovery Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.865 0.949
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member] | Maximum [Member] | Fair Value Unobservable Inputs, Duration [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 4.3 9.1
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member] | Weighted Average [Member] | Fair Value Unobservable Inputs, Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.123 0.090
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member] | Weighted Average [Member] | Fair Value Unobservable Inputs, Recovery Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.550 0.577
Level 3 [Member] | Loans and Securities Backed by Commercial Real Estate [Member] | Weighted Average [Member] | Fair Value Unobservable Inputs, Duration [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 1.8 5.0
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Total financial assets at fair value | $ $ 152 $ 131
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member] | Minimum [Member] | Fair Value Unobservable Inputs, Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.004 0.006
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member] | Minimum [Member] | Fair Value Unobservable Inputs, Cumulative Loss Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.001 0.034
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member] | Minimum [Member] | Fair Value Unobservable Inputs, Duration [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 1.2 0.9
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member] | Maximum [Member] | Fair Value Unobservable Inputs, Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.266 0.157
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member] | Maximum [Member] | Fair Value Unobservable Inputs, Cumulative Loss Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.434 0.456
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member] | Maximum [Member] | Fair Value Unobservable Inputs, Duration [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 17.2 16.1
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member] | Weighted Average [Member] | Fair Value Unobservable Inputs, Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.070 0.063
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member] | Weighted Average [Member] | Fair Value Unobservable Inputs, Cumulative Loss Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.177 0.208
Level 3 [Member] | Loans and Securities Backed by Residential Real Estate [Member] | Weighted Average [Member] | Fair Value Unobservable Inputs, Duration [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 6.5 6.5
Level 3 [Member] | Corporate debt instruments [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Total financial assets at fair value | $ $ 1,318 $ 797
Level 3 [Member] | Corporate debt instruments [Member] | Minimum [Member] | Fair Value Unobservable Inputs, Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.000 0.006
Level 3 [Member] | Corporate debt instruments [Member] | Minimum [Member] | Fair Value Unobservable Inputs, Recovery Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.090 0.000
Level 3 [Member] | Corporate debt instruments [Member] | Minimum [Member] | Fair Value Unobservable Inputs, Duration [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 2.0 0.3
Level 3 [Member] | Corporate debt instruments [Member] | Maximum [Member] | Fair Value Unobservable Inputs, Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.180 0.306
Level 3 [Member] | Corporate debt instruments [Member] | Maximum [Member] | Fair Value Unobservable Inputs, Recovery Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.699 0.736
Level 3 [Member] | Corporate debt instruments [Member] | Maximum [Member] | Fair Value Unobservable Inputs, Duration [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 28.5 25.5
Level 3 [Member] | Corporate debt instruments [Member] | Weighted Average [Member] | Fair Value Unobservable Inputs, Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.071 0.095
Level 3 [Member] | Corporate debt instruments [Member] | Weighted Average [Member] | Fair Value Unobservable Inputs, Recovery Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 0.520 0.587
Level 3 [Member] | Corporate debt instruments [Member] | Weighted Average [Member] | Fair Value Unobservable Inputs, Duration [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value Unobservable Inputs, Asset 4.5 4.0