Discontinued Operations - Assets and Liabilities of Discontinued Operations Were Considered Held for Sale (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other assets		$ 440
Credit Card Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net		21,185
Other assets		269
Assets of discontinued operations		21,454
Deposits in domestic offices - noninterest bearing		35
Other liabilities		876
Liabilities of discontinued operations		$ 911