Investment in Lease Financing (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009	Dec. 31, 2008
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accumulated allowance for uncollectible minimum lease payments	$ 2,255	[1]	$ 3,004	[1]	$ 3,749	$ 2,787
Leases [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accumulated allowance for uncollectible minimum lease payments	$ 79		$ 112

[1] At December 31, 2011 and 2010, includes $30 and $52 of cash, $7 of other short-term investments, $50 and $29 of commercial mortgage loans, $223 and $241 of home equity loans, $259 and $648 of automobile loans, ($10) and ($14) of ALLL, $4 and $7 of other assets, $4 and $12 of other liabilities, $191 and $692 of long-term debt from consolidated VIEs that are included in their respective captions. See Note 11.