Long-Term Debt Partnership's Long-Term Debt Schedule (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Long-Term Debt Disclosure [Abstract]
Senior notes	$ 5,089us-gaap_DebtInstrumentFaceAmount	$ 5,089us-gaap_DebtInstrumentFaceAmount
Revolving loans	2,087us-gaap_LineOfCredit	1,504us-gaap_LineOfCredit
Unamortized premium and discounts	45	48
Long-term debt	7,221us-gaap_LongTermDebtNoncurrent	6,641us-gaap_LongTermDebtNoncurrent
Total credit facility limit	2,500	2,000
Revolving loans	(2,087)us-gaap_LineOfCredit	(1,504)us-gaap_LineOfCredit
Letters of credit	(16)	(23)
Total available	$ 397	$ 473

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

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- Definition

The amount of debt discount (net of debt premium) that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

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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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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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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