Trading Cash Instruments - Schedule of Level 3 Assets, and Ranges and Weighted Averages of Significant Unobservable Inputs (Detail) $ in Millions	Sep. 30, 2022 USD ($) yr	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($) yr
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total financial assets at fair value | $	$ 694,838	$ 738,615	$ 715,812
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total financial assets at fair value | $	29,275	$ 28,884	24,083
Level 3 | Loans and securities backed by commercial real estate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total financial assets at fair value | $	$ 55		$ 137
Level 3 | Loans and securities backed by commercial real estate | Minimum | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.068		0.028
Level 3 | Loans and securities backed by commercial real estate | Minimum | Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.470		0.051
Level 3 | Loans and securities backed by commercial real estate | Minimum | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	1.2		0.1
Level 3 | Loans and securities backed by commercial real estate | Maximum | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.340		0.285
Level 3 | Loans and securities backed by commercial real estate | Maximum | Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.617		0.865
Level 3 | Loans and securities backed by commercial real estate | Maximum | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	3.7		4.3
Level 3 | Loans and securities backed by commercial real estate | Weighted Average | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.202		0.123
Level 3 | Loans and securities backed by commercial real estate | Weighted Average | Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.531		0.550
Level 3 | Loans and securities backed by commercial real estate | Weighted Average | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	2.1		1.8
Level 3 | Loans and securities backed by residential real estate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total financial assets at fair value | $	$ 110		$ 152
Level 3 | Loans and securities backed by residential real estate | Minimum | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.010		0.004
Level 3 | Loans and securities backed by residential real estate | Minimum | Cumulative loss rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.110		0.001
Level 3 | Loans and securities backed by residential real estate | Minimum | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	1.1		1.2
Level 3 | Loans and securities backed by residential real estate | Maximum | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.230		0.266
Level 3 | Loans and securities backed by residential real estate | Maximum | Cumulative loss rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.350		0.434
Level 3 | Loans and securities backed by residential real estate | Maximum | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	10.8		17.2
Level 3 | Loans and securities backed by residential real estate | Weighted Average | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.097		0.070
Level 3 | Loans and securities backed by residential real estate | Weighted Average | Cumulative loss rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.208		0.177
Level 3 | Loans and securities backed by residential real estate | Weighted Average | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	6.5		6.5
Level 3 | Corporate debt instruments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total financial assets at fair value | $	$ 1,352		$ 1,318
Level 3 | Corporate debt instruments | Minimum | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.012		0.000
Level 3 | Corporate debt instruments | Minimum | Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.170		0.090
Level 3 | Corporate debt instruments | Minimum | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.5		2.0
Level 3 | Corporate debt instruments | Maximum | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.330		0.180
Level 3 | Corporate debt instruments | Maximum | Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.700		0.699
Level 3 | Corporate debt instruments | Maximum | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	21.4		28.5
Level 3 | Corporate debt instruments | Weighted Average | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.066		0.071
Level 3 | Corporate debt instruments | Weighted Average | Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.516		0.520
Level 3 | Corporate debt instruments | Weighted Average | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	4.7		4.5
Level 3 | Other
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total financial assets at fair value | $	$ 311		$ 282
Level 3 | Other | Minimum | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.040		0.011
Level 3 | Other | Minimum | Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	3.9
Level 3 | Other | Minimum | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.8		0.9
Level 3 | Other | Maximum | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.416		0.448
Level 3 | Other | Maximum | Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	4.2
Level 3 | Other | Maximum | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	13.0		5.2
Level 3 | Other | Weighted Average | Yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.115		0.094
Level 3 | Other | Weighted Average | Recovery rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	4.0
Level 3 | Other | Weighted Average | Duration (years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	5.0		2.4