Derivative Instruments - Asset and Liability Management Derivative Positions of Company (Parenthetical) (Detail) - Asset and Liability Management Positions [Member] - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Notional Value, Assets	$ 64,143	$ 64,041
Notional Value, Liabilities	52,972	54,020
Fair Value, Liabilities	521	548
Swap [Member] | Visa Class B Shares [Member]
Derivative [Line Items]
Notional Value, Liabilities	1,800	1,800
Fair Value, Liabilities	$ 139	$ 182
Derivative Liability Average Remaining Maturity Period	1 year 9 months	2 years 6 months
Underwriting Purchase and Sale Commitments [Member]
Derivative [Line Items]
Notional Value, Assets	$ 602	$ 47
Notional Value, Liabilities	$ 602	$ 47