Related Party Transactions (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended					6 Months Ended	3 Months Ended
	Jun. 30, 2013 Successor	Jun. 30, 2012 Successor		Jun. 30, 2012 Successor		Jun. 30, 2013 Successor	Mar. 25, 2012 Predecessor
Related Party Transaction
Transportation and storage of natural gas	$ 3	$ 2		$ 2		$ 6	$ 1
Operating, maintenance and general	16	11	[1]	50	[1]	32	14
Interest income - affiliates	$ 0	$ 1		$ 1		$ 1	$ 2

[1] Primarily represents corporate charges for employee expenses related to the merger with ETE offset by expenses attributable to services provided by Panhandle on behalf of affiliated companies.