Guarantor Condensed Consolidating Statements of Operations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Revenues	$ 747,123	$ 652,352
Costs and expenses	(580,741)	(492,695)
Gross profits	166,382	159,657
General and administrative expenses	(56,010)	(30,923)
Losses on divestitures and impairment charges, net	(2,812)	(969)
Operating income	107,560	127,765
Interest expense	(44,996)	(32,769)
Equity in subsidiaries	0	0
Other (expense) income, net	1,534	(984)
Income from continuing operations before income taxes	64,098	94,012
Benefit (provision for income taxes	(22,707)	(35,290)
Net income	41,391	58,722
Net income attributable to noncontrolling interests	(289)	(1,102)
Net income attributable to common stockholders	41,102	57,620
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0	0
Costs and expenses	0	0
Gross profits	0	0
General and administrative expenses	(267)	(262)
Losses on divestitures and impairment charges, net	0	0
Operating income	(267)	(262)
Interest expense	(40,593)	(31,035)
Equity in subsidiaries	66,917	77,420
Other (expense) income, net	0	0
Income from continuing operations before income taxes	26,057	46,123
Benefit (provision for income taxes	15,045	11,497
Net income	41,102	57,620
Net income attributable to noncontrolling interests	0	0
Net income attributable to common stockholders	41,102	57,620
Subsidiary Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0
Costs and expenses	0
Gross profits	0
General and administrative expenses	(8,979)
Losses on divestitures and impairment charges, net	0
Operating income	(8,979)
Interest expense	(2,652)
Equity in subsidiaries	19,394
Other (expense) income, net	(2)
Income from continuing operations before income taxes	7,761
Benefit (provision for income taxes	4,691
Net income	12,452
Net income attributable to noncontrolling interests	0
Net income attributable to common stockholders	12,452
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	110,165
Costs and expenses	(78,197)
Gross profits	31,968
General and administrative expenses	0
Losses on divestitures and impairment charges, net	(66)
Operating income	31,902
Interest expense	0
Equity in subsidiaries	384
Other (expense) income, net	1
Income from continuing operations before income taxes	32,287
Benefit (provision for income taxes	(12,863)
Net income	19,424
Net income attributable to noncontrolling interests	0
Net income attributable to common stockholders	19,424
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	636,958	652,352
Costs and expenses	(502,544)	(492,695)
Gross profits	134,414	159,657
General and administrative expenses	(46,764)	(30,661)
Losses on divestitures and impairment charges, net	(2,746)	(969)
Operating income	84,904	128,027
Interest expense	(1,751)	(1,734)
Equity in subsidiaries	0	0
Other (expense) income, net	1,535	(984)
Income from continuing operations before income taxes	84,688	125,309
Benefit (provision for income taxes	(29,580)	(46,787)
Net income	55,108	78,522
Net income attributable to noncontrolling interests	0	0
Net income attributable to common stockholders	55,108	78,522
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Revenues	0	0
Costs and expenses	0	0
Gross profits	0	0
General and administrative expenses	0	0
Losses on divestitures and impairment charges, net	0	0
Operating income	0	0
Interest expense	0	0
Equity in subsidiaries	(86,695)	(77,420)
Other (expense) income, net	0	0
Income from continuing operations before income taxes	(86,695)	(77,420)
Benefit (provision for income taxes	0	0
Net income	(86,695)	(77,420)
Net income attributable to noncontrolling interests	(289)	(1,102)
Net income attributable to common stockholders	$ (86,984)	$ (78,522)