Long-Term Debt - Schedule of Long-Term Debt (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Senior secured debt	$ 20,070us-gaap_SecuredDebt	$ 18,181us-gaap_SecuredDebt
Total debt (average life of 6.1 years, rates averaging 5.6%)	29,645us-gaap_LongTermDebt	28,376us-gaap_LongTermDebt
Total debt (average life of 6.1 years, rates averaging 5.6%)	29,645us-gaap_LongTermDebt	28,376us-gaap_LongTermDebt
Less amounts due within one year	338us-gaap_LongTermDebtCurrent	786us-gaap_LongTermDebtCurrent
Long-term debt	29,307us-gaap_LongTermDebtNoncurrent	27,590us-gaap_LongTermDebtNoncurrent
Senior Secured Asset-Based Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term line of credit	2,880	2,440
Senior Secured Term Loan Facilities [Member]
Debt Instrument [Line Items]
Term loans	5,517	5,598
Senior Secured Notes [Member]
Debt Instrument [Line Items]
Senior secured debt	11,100	9,695
Other Senior Secured Debt [Member]
Debt Instrument [Line Items]
Other senior secured debt (effective interest rate of [6.3]%)	573	448
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Senior unsecured notes	$ 9,575	$ 10,195

Senior secured term loan facilities.

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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.

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Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Carrying value as of the balance sheet date of other collateralized debt obligations.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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