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Interest in entities which guarantee our debt issuances, expressed as a percentage

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non vested restricted stock excluded from basic weighted average common shares.

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Percentage of ownership in subsidiaries.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The portion of net Income or Loss attributable to the noncontrolling interest (if any) deducted in order to derive the portion attributable to the parent.

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Appreciation or loss in value (before reclassification adjustment) of the total of unsold securities during the period being reported on, net of tax. Reclassification adjustments include: (1) the unrealized holding gain (loss), net of tax, at the date of the transfer for a debt security from the held-to-maturity category transferred into the available-for-sale category. Also includes the unrealized gain (loss) at the date of transfer for a debt security from the available-for-sale category transferred into the held-to-maturity category; (2) the unrealized gains (losses) realized upon the sale of securities, after tax; and (3) the unrealized gains (losses) realized upon the write-down of securities, after tax.

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Tax effect on gross appreciation or the gross loss in value of the total of unsold securities during the period being reported on.

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Dividends received on equity and other investments during the current period.

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Basis of Presentation (Details Textuals) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010	Dec. 30, 2010 ENP LP Investment [Member]	Dec. 30, 2010 GP LLC [Member]
Business Acquisition [Line Items]
Ownership percentage in subsidiaries						46.00%	100.00%
Cost basis of investment in VNR					$ 93,000,000
Interest in guarantor subsidiaries	100.00%		100.00%
Basis of Presentation (Textuals) [Abstract]
Net income attributable to noncontrolling interest	0	2,130,000	0	20,408,000
Weighted average common shares - basic restricted stock	3.40	3.40	3.50	3.30
Net unrealized losses on available-for-sale securities, net of tax	3,949,000	0	6,925,000	0
Unrealized loss on short term investment, tax	2,420,000	0	4,244,000	0
Distribution on Vanguard common units	$ 1,800,000		$ 5,300,000