Related Party Transactions (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended		3 Months Ended
	Mar. 31, 2012 Successor		Mar. 31, 2013 Successor	Mar. 25, 2012 Predecessor
Related Party Transaction
Transportation and storage of natural gas	$ 0		$ 3	$ 1
Operation and maintenance and general	39	[1]	16	14
Interest Income	$ 0		$ 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.