Debt Obligations 1 (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Debt Instrument Line Items
Total Long Term Debt Carrying Value	$ 3,521,806	$ 3,521,989
Long Term Debt Fair Value	3,822,328	3,689,892
Credit Facilities	195,479	297,051
Credit Facilities Fair Value	195,487	301,312
Total consolidated debt obligations	3,717,285	3,819,040
Total consolidated debt obligations fair value	4,017,815	3,991,204
Less current portion of long-term debt	816,272	1,083
Less short-term debt	195,479	297,051
Total long-term debt	2,705,534	3,520,906
Senior Notes due 2024 [Member] \| Southern Union [Member]
Debt Instrument Line Items
Interest Rate	7.60%	7.60%
Total Long Term Debt Carrying Value	359,765	359,765
Long Term Debt Fair Value	428,300	392,144
Senior Notes Due 2029 [Member] \| Southern Union [Member]
Debt Instrument Line Items
Interest Rate	8.25%	8.25%
Total Long Term Debt Carrying Value	300,000	300,000
Long Term Debt Fair Value	377,403	332,922
Senior Notes Due 2029 [Member] \| Panhandle [Member]
Debt Instrument Line Items
Interest Rate	7.00%	7.00%
Total Long Term Debt Carrying Value	66,305	66,305
Long Term Debt Fair Value	70,068	69,911
First Mortgage Bonds due 2020 to 2027 [Member] \| Southern Union [Member]
Debt Instrument Line Items
Interest Rate Minimum	7.24%	7.24%
Interest Rate Maximum	9.44%	9.44%
Total Long Term Debt Carrying Value	19,500	19,500
Long Term Debt Fair Value	23,558	21,473
Junior Subordinated Notes due 2066 [Member] \| Southern Union [Member]
Debt Instrument Line Items
Interest Rate	7.20%	7.20%
Total Long Term Debt Carrying Value	600,000	600,000
Long Term Debt Fair Value	575,280	609,743
Term Loan 2013 [Member] \| Southern Union [Member]
Debt Instrument Line Items
Total Long Term Debt Carrying Value	250,000	250,000
Long Term Debt Fair Value	252,491	249,915
Note Payable [Member] \| Southern Union [Member]
Debt Instrument Line Items
Total Long Term Debt Carrying Value	8,019	8,297
Long Term Debt Fair Value	8,019	8,297
Senior Notes due 2013 [Member] \| Panhandle [Member]
Debt Instrument Line Items
Interest Rate	6.05%	6.05%
Total Long Term Debt Carrying Value	250,000	250,000
Long Term Debt Fair Value	273,260	268,988
Senior Notes due 2017 [Member] \| Panhandle [Member]
Debt Instrument Line Items
Interest Rate	6.20%	6.20%
Total Long Term Debt Carrying Value	300,000	300,000
Long Term Debt Fair Value	346,413	322,893
Senior Notes due 2019 [Member] \| Panhandle [Member]
Debt Instrument Line Items
Interest Rate	8.125%	8.125%
Total Long Term Debt Carrying Value	150,000	150,000
Long Term Debt Fair Value	183,813	169,671
Senior Notes due 2018 [Member] \| Panhandle [Member]
Debt Instrument Line Items
Interest Rate	7.00%	7.00%
Total Long Term Debt Carrying Value	400,000	400,000
Long Term Debt Fair Value	472,416	442,120
Term Loan 2012 [Member] \| Panhandle [Member]
Debt Instrument Line Items
Total Long Term Debt Carrying Value	815,391	815,391
Long Term Debt Fair Value	808,481	799,084
Net Premiums [Member] \| Panhandle [Member]
Debt Instrument Line Items
Total Long Term Debt Carrying Value	2,826	2,731
Long Term Debt Fair Value	2,826	2,731
Southern Union [Member]
Debt Instrument Line Items
Total Long Term Debt Carrying Value	1,537,284	1,537,562
Long Term Debt Fair Value	1,665,051	1,614,494
Panhandle [Member]
Debt Instrument Line Items
Total Long Term Debt Carrying Value	1,984,522	1,984,427
Long Term Debt Fair Value	$ 2,157,277	$ 2,075,398

Including current and noncurrent portions, aggregate fair value of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Amount borrowed under the credit facility as of the balance sheet date.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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