Loans - Additional Information (Detail) (USD $)	30 Months Ended			3 Months Ended		6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013	Jun. 30, 2014 Consumer Loans [Member]	Jun. 30, 2013 Consumer Loans [Member]	Jun. 30, 2014 Consumer Loans [Member]	Jun. 30, 2013 Consumer Loans [Member]	Dec. 31, 2013 Consumer Loans [Member]	Jun. 30, 2014 Residential Mortgage And Home Equity [Member] Consumer Loans [Member]		Dec. 31, 2013 Residential Mortgage And Home Equity [Member] Consumer Loans [Member]		Jun. 30, 2014 Parent And Other Subsidiaries Of Common Parent [Member]	Dec. 31, 2013 Parent And Other Subsidiaries Of Common Parent [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 72,198,000,000	$ 67,695,000,000	$ 66,705,000,000	$ 19,165,000,000		$ 19,165,000,000		$ 19,201,000,000	$ 18,011,000,000		$ 17,837,000,000		$ 5,080,000,000	$ 5,328,000,000
Net deferred origination fees	6,000,000	23,000,000
Net unamortized premium on loans	14,000,000	16,000,000
Total nonaccruing loans	1,107,000,000	1,305,000,000		948,000,000		948,000,000		1,026,000,000	948,000,000	[1],[2],[3]	1,026,000,000	[1],[2],[3]
Residential mortgage loan delinquency carried at lower of amortized cost or fair value less cost to sell	983,000,000	1,074,000,000							849,000,000		866,000,000
Commercial loans removed from TDR classification	$ 0
Weighted average rate of reduction				1.52%	2.07%	1.51%	2.06%

[1] Residential mortgage nonaccrual loans for all periods does not include guaranteed loans purchased from the Government National Mortgage Association ("GNMA"). Repayment of these loans are predominantly insured by the Federal Housing Administration and as such, these loans have different risk characteristics from the rest of our customer loan portfolio.

[2] Nonaccrual residential mortgages includes all receivables which are 90 or more days contractually delinquent as well as loans discharged under Chapter 7 bankruptcy and not re-affirmed and second lien loans where the first lien loan that we own or service is 90 or more days contractually delinquent.

[3] At June 30, 2014 and December 31, 2013, residential mortgage loan nonaccrual balances include $849 million and $866 million, respectively, of loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell.