Summary of Significant Accounting Policies and Other Matters 3 (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current
Natural gas	$ 158,223	$ 185,583
Materials and supplies	36,122	31,380
NGL	9,890	9,912
Total Current	204,235	226,875
Non-Current
Natural gas	2,643	5,715
Energy Related Inventory	206,878	232,590
Transportation And Storage [Member]
Current
Natural gas	95,916	129,727
Materials and supplies	18,823	17,527
NGL	0	0
Non-Current
Natural gas	2,643	5,715
Energy Related Inventory	117,382	152,969
Gathering And Processing [Member]
Current
Natural gas	0	0
Materials and supplies	12,543	9,973
NGL	9,890	9,912
Non-Current
Natural gas	0	0
Energy Related Inventory	22,433	19,885
Distribution [Member]
Current
Natural gas	62,307	55,856
Materials and supplies	4,756	3,880
NGL	0	0
Non-Current
Natural gas	0	0
Energy Related Inventory	$ 67,063	$ 59,736

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Carrying amount as of the balance sheet date of natural gas inventory expected to be consumed within the next twelve months.

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No definition available.

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- Definition

Carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies relating to a source of usable power held for future sale or future use in manufacturing or production process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

-Article 5

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-Name Accounting Standards Codification

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Carrying amount as of the balance sheet date of liquid hydrocarbon components recovered from natural gas.

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Carrying amount as of the balance sheet date of natural gas stored underground in depleted gas reservoirs, aquifers, or salt caverns to meet future seasonal and peak load demands and also as insurance against unforeseen supply disruptions, and deemed to be a noncurrent asset because it is not expected to be used within 12 months or in the normal operating cycle.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 43

-Chapter 3

-Section A

-Paragraph 4, 5

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-Name Statement of Financial Accounting Standard (FAS)

-Number 19

-Paragraph 59

-Subparagraph A-CC

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

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- Definition

Aggregated amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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