Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Fair value of securities received as collateral against derivative assets.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after effects of master netting arrangements, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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Fair value of securities pledged as collateral against derivative liabilities.

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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Derivative Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Derivative [Line Items]
Net unrealized pre-tax gains related to hedged loans held for sale, commitments to originate loans for sale and commitments to sell loans	$ 38,000,000		$ 38,000,000		$ 18,000,000
Aggregate fair value of derivative financial instruments in a liability position	85,000,000		85,000,000		59,000,000
Net liability positions with counterparties	81,000,000		81,000,000		55,000,000
Aggregate fair value of derivative financial instruments in asset position	15,000,000		15,000,000		23,000,000
Net asset positions with counterparties	11,000,000		11,000,000		19,000,000
Counterparties posted collateral relating to positions	11,000,000		11,000,000		22,000,000
Counterparties [Member]
Derivative [Line Items]
Post collateral requirements relating to positions	79,000,000		79,000,000		52,000,000
Clearinghouse Credit Facilities [Member]
Derivative [Line Items]
Post collateral requirements relating to positions	265,000,000		265,000,000		99,000,000
Aggregate fair value of derivative financial instruments in a net liability position	177,000,000		177,000,000		50,000,000
Interest Rate Swap Agreements [Member]
Derivative [Line Items]
Increase in net interest income due to interest rate swap agreements	9,000,000	$ 11,000,000	30,000,000	$ 33,000,000
Interest Rate Contracts [Member]
Derivative [Line Items]
Notional amounts of derivative contracts entered into for trading account purposes	21,200,000,000		21,200,000,000		18,400,000,000
Foreign Currency and Other Option and Futures Contracts [Member]
Derivative [Line Items]
Notional amounts of derivative contracts entered into for trading account purposes	891,000,000		891,000,000		$ 1,600,000,000
Credit Risk Derivative [Member]
Derivative [Line Items]
Aggregate fair value of derivative financial instruments in a net liability position	19,000,000		19,000,000
Fair value of collateral already posted for derivative financial instruments	15,000,000		15,000,000
Fair value of additional collateral to be posted for derivative financial instruments	$ 4,000,000		$ 4,000,000