Segments and Operations by Geographic Area (Reconciliation of EBITDA to Consolidated Income) (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Interest expense, net	$ (10,045,000)	$ (8,951,000)
Depreciation	31,753,000	20,954,000
Amortization	(4,200,000)	(2,800,000)
Income (loss) from continuing operations before provision for income taxes	31,668,000	19,499,000
Segment, Continuing Operations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
EBITDA	73,500,000	49,200,000
Interest expense, net	(10,000,000)	(9,000,000)
Depreciation	31,753,000	20,717,000
Amortization	(4,200,000)	(2,800,000)
Property and Equipment [Member] | Segment, Continuing Operations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Depreciation	$ 27,600,000	$ 17,900,000