Allocation of Purchase Price To Acquired Assets and Liabilities Assumed(Detail) (Chesapeake Midstream Operating, L.L.C., USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 20, 2012
Chesapeake Midstream Operating, L.L.C.
Business Acquisition [Line Items]
Property, plant and equipment	$ 1,890,036
Intangible assets	263,262
Other	(6,702)
Total purchase price	$ 2,160,000	$ 2,160,000

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Amount of other assets expected to be realized or consumed before one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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The amount of property, plant, and equipment recognized as of the acquisition date.

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