Equity Investments And Membership Interests In Joint Ventures (Summarized Financial Information Of Equity Method Investments) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Equity Investments And Membership Interests In Joint Ventures [Abstract]
Revenues	$ 184,358	$ 172,933	$ 166,152
Gross profit	19,495	25,203	15,426
Income from operations	13,180	20,243	1,611
Net income (loss)	6,788	16,015	(1,797)
Current assets	94,644	48,202
Noncurrent assets	331,848	276,125
Total assets	426,492	324,327
Current liabilities	51,674	39,237
Noncurrent liabilities	120,494	99,350
Equity	254,163	185,639
Noncontrolling interest	161	101
Total liabilities and equity	$ 426,492	$ 324,327

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

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

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The amount of equity (capital), including the noncontrolling interest (if any), reported by an 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 income (loss) from continuing operations before extraordinary items 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 equity (capital) attributable to noncontrolling interests of 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 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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