Acquisitions 2014 TLLP Acquisition of Rockies Natural Gas Business (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended
Jun. 01, 2013	Dec. 02, 2014
Business Acquisition
Purchase Price Consideration	$ 2,420
Rockies Natural Gas Business
Business Acquisition
Date of acquisition		Dec. 02, 2014
Purchase Price Consideration		$ 2,500

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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

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-Name Accounting Standards Codification

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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