Related Party Transactions (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended					3 Months Ended	12 Months Ended		3 Months Ended		12 Months Ended				3 Months Ended		12 Months Ended
	Dec. 31, 2012 Successor	Dec. 31, 2012 Successor Southern Union		Dec. 31, 2012 Successor Affiliated Entity		Mar. 25, 2012 Predecessor	Dec. 31, 2011 Predecessor	Dec. 31, 2010 Predecessor	Mar. 25, 2012 Predecessor Southern Union		Dec. 31, 2011 Predecessor Southern Union		Dec. 31, 2010 Predecessor Southern Union		Mar. 25, 2012 Predecessor Affiliated Entity		Dec. 31, 2011 Predecessor Affiliated Entity		Dec. 31, 2010 Predecessor Affiliated Entity
Operation and maintenance:
Transportation and storage of natural gas		$ 7	[1]						$ 1	[1]	$ 3	[1]	$ 3	[1]
Management and royalty fees				5											5		20		19
Cost of Services				47											9		32		31
Other expenses (2)				9	[2]										0	[2]	6	[2]	5	[2]
Other income, net:
Interest income	$ 2	$ 2				$ 2	$ 9	$ 9	$ 2		$ 9		$ 9

[1] Represents transportation and storage revenues with ETC, a subsidiary of ETP (in the successor period) and MGE, a Southern Union division.

[2] Represents primarily insurance costs and corporate charges for merger-related employee expenses from ETE offset by expenses attributable to services provided by Panhandle on behalf of other affiliate companies.