Variable Interest Entities - Summary of Assets and Liabilities of Consolidated Secured Financing VIEs (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Variable Interest Entity [Line Items]
Cash	$ 197	$ 215
Receivables, net	29,284	43,201
Available-for-sale investments	80	188
Long-term debt	28,426	39,790
Variable Interest Entity [Member]
Variable Interest Entity [Line Items]
Cash	6
Receivables, net	4,197	4,486
Available-for-sale investments		4
Subtotal, Consolidated Assets	4,203	4,490
Other liabilities	(39)
Long-term debt	2,878	3,315
Subtotal, Consolidated Liabilities	$ 2,839	$ 3,315

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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+ Details

- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References+ Details

- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References+ Details

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References+ Details