Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Allowance for Doubtful Accounts Receivable, Current	$ 7	$ 1
Other, accumulated amortization of debt issuance costs	28	24
Intangible assets, accumulated amortization	212	107
Series A Preferred Units, redemption amount of $38 and $38	$ 38	$ 38
Common units, authorized	412,681,151	214,287,955
Common units, issued	409,406,482	210,850,232
Common units, outstanding	409,406,482	210,850,232
Class F Units [Member]
Partners' Capital Account, Units	6,274,483	6,274,483

Carrying amount of accumulated amortization of long-term deferred finance costs capitalized at the end of the reporting period.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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The number of limited partner units authorized to be issued.

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The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

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Aggregate amount of redemption requirements for each class or type of redeemable stock classified as temporary equity for each of the five years following the latest balance sheet date. The redemption requirement does not constitute an unconditional obligation that will be settled in a variable number of shares constituting a monetary value predominantly indexed to (a) a fixed monetary amount known at inception, (b) an amount inversely correlated with the residual value of the entity, or (c) an amount determined by reference to something other than the fair value of issuer's stock. Does not include mandatorily redeemable stock. The exception is if redemption is required upon liquidation or termination of the reporting entity.

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