Acquisitions 2014 TLLP Acquisition of Rockies Natural Gas Business (Details) - USD ($) $ in Millions	Dec. 02, 2014	Jun. 01, 2013
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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