Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

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-Name Regulation S-X (SX)

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Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

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Face (par) amount of debt instrument at time of issuance.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Weighted average interest rate of short-term debt outstanding.

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Bank Financing and Debt Additional Disclosures (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Nov. 30, 2014
Debt Disclosure [Abstract]
Face value of debt	7,150,000,000us-gaap_DebtInstrumentFaceAmount	$ 6,440,000,000us-gaap_DebtInstrumentFaceAmount
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Borrowings outstanding	0
Availability under the credit facility	2,490,000,000
Maximum borrowing capacity under the credit facility	2,500,000,000.0		2,000,000,000.0
Commercial Paper [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity under the credit facility	2,500,000,000.0		2,000,000,000
Weighted average interest rate	0.46%	0.28%
Consolidated Leverage Ratio [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility covenant description	4.5x
Credit facility covenant compliance	2.1x
Interest rate swap [Member]
Derivatives [Line Items]
Notional amount of derivative	600,000,000