Supplemental Guarantor Information (Supplemental Condensed Consolidated Statement of Cash Flows) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Operating activities
Net cash used in operating activities	$ (146,903)	$ (109,271)
Investing activities
Net cash used in investing activities	(2,687)	(178,628)
Financing activities
Borrowings under revolving credit facilities	135,000	99,000
Payments on revolving credit facilities	(55,000)	(99,000)
Proceeds from issuance of senior notes	58,956	198,478
Proceeds from issuances of notes payable	448	5,894
Principal payments on notes payable	(6,815)	(1,562)
Debt issuance costs	(2,817)	(5,132)
Net proceeds from issuances of common stock		81,890
Repurchases of common stock upon vesting of restricted stock awards	(859)
Excess tax benefit on stock-based compensation		37
Net cash provided by financing activities	128,913	279,605
Net increase (decrease) in cash and cash equivalents	(20,677)	(8,294)
Cash and cash equivalents, Beginning of period	33,462	109,998
Cash and cash equivalents, End of period	12,785	101,704
Parent [Member]
Operating activities
Net cash used in operating activities	(5,168)	(767)
Investing activities
Net cash used in investing activities	(148,667)	(287,323)
Financing activities
Borrowings under revolving credit facilities	135,000	99,000
Payments on revolving credit facilities	(55,000)	(99,000)
Proceeds from issuance of senior notes	58,956	198,478
Debt issuance costs	(2,817)	(5,132)
Net proceeds from issuances of common stock		81,890
Repurchases of common stock upon vesting of restricted stock awards	(859)
Excess tax benefit on stock-based compensation		37
Net cash provided by financing activities	135,280	275,273
Net increase (decrease) in cash and cash equivalents	(18,555)	(12,817)
Cash and cash equivalents, Beginning of period	22,710	106,614
Cash and cash equivalents, End of period	4,155	93,797
Guarantor Subsidiaries [Member]
Operating activities
Net cash used in operating activities	(141,735)	(108,504)
Investing activities
Net cash used in investing activities	(2,398)	(178,628)
Financing activities
Proceeds from issuances of notes payable	448	5,894
Principal payments on notes payable	(6,815)	(1,562)
Payments from (and advances to) parent/subsidiary	148,378	287,323
Net cash provided by financing activities	142,011	291,655
Net increase (decrease) in cash and cash equivalents	(2,122)	4,523
Cash and cash equivalents, Beginning of period	10,752	3,384
Cash and cash equivalents, End of period	8,630	7,907
Elimination Entries [Member]
Investing activities
Net cash used in investing activities	148,378	287,323
Financing activities
Payments from (and advances to) parent/subsidiary	(148,378)	(287,323)
Net cash provided by financing activities	$ (148,378)	$ (287,323)