Debt Obligations - Schedule of Long-Term Debt Instruments (Details) (USD $) In Millions, unless otherwise specified								12 Months Ended																								12 Months Ended
	Dec. 31, 2012 Successor [Member]		Dec. 31, 2012 Successor [Member] Southern Union [Member]	Dec. 31, 2012 Successor [Member] Panhandle [Member]	Dec. 31, 2012 Successor [Member] Line of Credit [Member] Southern Union [Member]	Dec. 31, 2012 Successor [Member] 7.60% Senior Notes due 2024 [Member] Southern Union [Member]	Dec. 31, 2012 Successor [Member] 8.25% Senior Notes Due 2029 [Member] Southern Union [Member]	Dec. 31, 2012 Successor [Member] 7.24% to 9.44% First Mortgage Bonds due 2020 to 2027 [Member] Southern Union [Member]	Dec. 31, 2012 Successor [Member] 7.20% Junior Subordinated Notes due 2066 [Member] Southern Union [Member]		Dec. 31, 2011 Successor [Member] 7.20% Junior Subordinated Notes due 2066 [Member] Southern Union [Member]		Dec. 31, 2012 Successor [Member] Term Loan due 2013 [Member] Southern Union [Member]	Dec. 31, 2012 Successor [Member] Note Payable [Member] Southern Union [Member]	Dec. 31, 2012 Successor [Member] Unamortized fair value adjustment [Member] Southern Union [Member]	Dec. 31, 2012 Successor [Member] Unamortized fair value adjustment [Member] Panhandle [Member]	Dec. 31, 2012 Successor [Member] 6.05% Senior Notes due 2013 [Member] Panhandle [Member]	Dec. 31, 2012 Successor [Member] 6.20% Senior Notes due 2017 [Member] Panhandle [Member]	Dec. 31, 2012 Successor [Member] 8.125% Senior Notes due 2019 [Member] Panhandle [Member]	Dec. 31, 2012 Successor [Member] 7.00% Senior Notes due 2029 [Member] Panhandle [Member]	Dec. 31, 2012 Successor [Member] 7.00% Senior Notes due 2018 [Member] Panhandle [Member]	Dec. 31, 2012 Successor [Member] Term Loan due 2012 [Member] Panhandle [Member]	Dec. 31, 2012 Successor [Member] Term Loan due 2015 [Member] Panhandle [Member]	Dec. 31, 2012 Successor [Member] Net premiums on long-term debt [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member]		Dec. 31, 2011 Predecessor [Member] Southern Union [Member]	Dec. 31, 2011 Predecessor [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member] Line of Credit [Member] Southern Union [Member]	Dec. 31, 2011 Predecessor [Member] 7.60% Senior Notes due 2024 [Member] Southern Union [Member]	Dec. 31, 2011 Predecessor [Member] 8.25% Senior Notes Due 2029 [Member] Southern Union [Member]	Dec. 31, 2011 Predecessor [Member] 7.24% to 9.44% First Mortgage Bonds due 2020 to 2027 [Member] Southern Union [Member]	Dec. 31, 2011 Predecessor [Member] 7.20% Junior Subordinated Notes due 2066 [Member] Southern Union [Member]		Dec. 31, 2011 Predecessor [Member] Term Loan due 2013 [Member] Southern Union [Member]	Dec. 31, 2011 Predecessor [Member] Note Payable [Member] Southern Union [Member]	Dec. 31, 2011 Predecessor [Member] Unamortized fair value adjustment [Member] Southern Union [Member]	Dec. 31, 2011 Predecessor [Member] Unamortized fair value adjustment [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member] 6.05% Senior Notes due 2013 [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member] 6.20% Senior Notes due 2017 [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member] 8.125% Senior Notes due 2019 [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member] 7.00% Senior Notes due 2029 [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member] 7.00% Senior Notes due 2018 [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member] Term Loan due 2012 [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member] Term Loan due 2015 [Member] Panhandle [Member]	Dec. 31, 2011 Predecessor [Member] Net premiums on long-term debt [Member] Panhandle [Member]	Dec. 31, 2012 LIBOR [Member] 7.20% Junior Subordinated Notes due 2066 [Member] Southern Union [Member]	Dec. 31, 2012 Revolver 2012 [Member] Annualized Interest Rate [Member] LIBOR [Member]	Dec. 31, 2012 Revolver 2012 [Member] Commitment Fee Rate [Member] LIBOR [Member]
Long Term Debt Obligations:
Senior Notes						$ 360	$ 300										$ 250	$ 300	$ 150	$ 66	$ 400									$ 360	$ 300								$ 250	$ 300	$ 150	$ 66	$ 400
Long-term Debt			1,316	1,757				0	600	[1]	600	[1]	0	7								0	455	0			1,537	1,966				20	600	[1]	250	7								797	0	3
Unamortized fair value adjustments															49	136																					0	0
Credit Facilities					210																								200
Total consolidated debt obligations	3,283																								3,703
Less: Current portion of long-term debt	(259)																								(343)
Less: Short-term debt	0	[2]																							200	[2]
Total long-term debt	$ 3,024																								$ 3,160
Debt instrument, three month LIBOR, basis spread on variable rate																																															3.0175%	1.625%	0.25%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum								7.24%																								7.24%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum								9.44%																								9.44%
Debt Instrument, Interest Rate, Stated Percentage						7.60%	8.25%		7.20%								6.05%	6.20%	8.125%	7.00%	7.00%									7.60%	8.25%		7.20%						6.05%	6.20%	8.125%	7.00%	7.00%

[1] (1) Effective November 1, 2011, the interest rate on the Junior Subordinated Notes changed to a variable rate based upon the three-month LIBOR rate plus 3.0175%, reset quarterly. See “Interest Rate Swaps” below for more information regarding the interest rate on these notes.

[2] (2) The Southern Union Credit Facility was included in short-term debt as of December 31, 2011, but not as of December 31, 2012. See discussion in “Credit Facilities” below.