Derivative Instruments - Asset and Liability Management Derivative Positions of Company (Parenthetical) (Detail) (Asset and Liability Management Positions [Member], USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Derivative [Line Items]
Derivative liability swap agreement notional value	$ 17,816	$ 14,730
Derivative liability swap agreement fair value	480	580
Derivative asset swap agreement notional value	26,822	28,119
Derivative liability swap agreement maturity
Underwriting Purchase And Sale Commitments [Member]
Derivative [Line Items]
Derivative liability swap agreement notional value	722
Derivative asset swap agreement notional value	722
Swap [Member] | Visa Class B [Member]
Derivative [Line Items]
Derivative liability swap agreement notional value	295
Derivative liability swap agreement fair value	$ 42
Derivative liability swap agreement maturity	4 years 4 days