Equity Investments And Membership Interests in Joint Ventures (Summarized financial information Of The Company's Equity Method Investees) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Equity Investments And Membership Interests In Joint Ventures [Abstract]
Revenues	$ 51,743	$ 44,470
Gross profit	2,475	6,084
Income from operations	(376)	3,643
Net income (loss)	(2,437)	2,283
Current assets	94,811		94,645
Noncurrent assets	361,918		332,124
Total assets	456,729		426,769
Current liabilities	62,260		51,953
Noncurrent liabilities	125,350		120,494
Equity	268,918		254,161
Noncontrolling interest	201		161
Total liabilities and equity	$ 456,729		$ 426,769

Equity Method Investment, Summarized Financial Information, Operating Income (Loss)

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The amount of assets reported by an equity method investment of the entity.

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Amount of equity, excluding noncontrolling interest, attributable to the equity method investment of the entity.

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The amount of gross profit (loss) reported by an equity method investment of the entity.

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The amount of liabilities and equity reported by an equity method investment of the entity.

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The amount of net income (loss) reported by an equity method investment of the entity.

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The amount of noncurrent assets reported by an equity method investment of the entity.

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The amount of noncurrent liabilities reported by an equity method investment of the entity.

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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