Guarantor/Non Guarantor Condensed Consolidated Financial Statements (Cash Flows (Unaudited)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities:	$ 9,627	$ 64,881
Cash flows from investing activities:
Purchases of property and equipment	(5,532)	(45,675)
Proceeds from sale of property and equipment	477	6,276
Proceeds from insurance recoveries	0	37
Net cash used in investing activities	(5,055)	(39,362)
Cash flows from financing activities:
Debt repayments	0	(25,002)
Debt issuance costs	(20)	(5)
Proceeds from exercise of options	0	601
Purchase of treasury stock	(43)	(359)
Proceeds from Contributions from Affiliates	0	0
Net cash used in financing activities	(63)	(24,765)
Net increase (decrease) in cash and cash equivalents	4,509	754
Beginning cash and cash equivalents	14,160	34,924
Ending cash and cash equivalents	18,669	35,678
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities:	24,998	86,131
Cash flows from investing activities:
Purchases of property and equipment	(5,424)	(44,667)
Proceeds from sale of property and equipment	432	6,250
Proceeds from insurance recoveries		37
Net cash used in investing activities	(4,992)	(38,380)
Cash flows from financing activities:
Debt repayments		(2)
Debt issuance costs	0	0
Proceeds from exercise of options		0
Purchase of treasury stock	0	0
Proceeds from Contributions from Affiliates	(14,242)	(45,022)
Net cash used in financing activities	(14,242)	(45,024)
Net increase (decrease) in cash and cash equivalents	5,764	2,727
Beginning cash and cash equivalents	(5,612)	(5,516)
Ending cash and cash equivalents	152	(2,789)
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities:	212	(3,030)
Cash flows from investing activities:
Purchases of property and equipment	(40)	(740)
Proceeds from sale of property and equipment	45	4
Proceeds from insurance recoveries		0
Net cash used in investing activities	5	(736)
Cash flows from financing activities:
Debt repayments		0
Debt issuance costs	0	0
Proceeds from exercise of options		0
Purchase of treasury stock	0	0
Proceeds from Contributions from Affiliates	(33)	(37)
Net cash used in financing activities	(33)	(37)
Net increase (decrease) in cash and cash equivalents	184	(3,803)
Beginning cash and cash equivalents	2,551	12,752
Ending cash and cash equivalents	2,735	8,949
Eliminations [Member]
Cash flows from financing activities:
Beginning cash and cash equivalents	0
Ending cash and cash equivalents	0
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Cash flows from operating activities:	(15,583)	(18,220)
Cash flows from investing activities:
Purchases of property and equipment	(68)	(268)
Proceeds from sale of property and equipment	0	22
Proceeds from insurance recoveries		0
Net cash used in investing activities	(68)	(246)
Cash flows from financing activities:
Debt repayments		(25,000)
Debt issuance costs	(20)	(5)
Proceeds from exercise of options		601
Purchase of treasury stock	(43)	(359)
Proceeds from Contributions from Affiliates	14,275	45,059
Net cash used in financing activities	14,212	20,296
Net increase (decrease) in cash and cash equivalents	(1,439)	1,830
Beginning cash and cash equivalents	17,221	27,688
Ending cash and cash equivalents	$ 15,782	$ 29,518