Consolidating Financial Information Supplemental Condensed Consolidating Statement of Cash Flows (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	$ 68,066	$ 95,071
Additions to property and equipment	(13,477)	(20,829)
Principal receipts from long-term receivables	10,276	9,922
Proceeds from sale of assets	137,449	60,188
Other	964	(558)
Cash flows provided by (used in) investing activities	135,212	48,723
Revolving credit borrowings	50,000	25,000
Revolving credit repayments	(50,000)	(25,000)
Payment of debt	(192,483)	(163,733)
Payment of debt issuance costs	0	(12,307)
Purchase of common stock	0	(21,170)
Restricted cash	(8,158)	(1,590)
Other	8,510	6,637
Intercompany transfers	0	0
Cash flows provided by (used in) financing activities	(192,131)	(192,163)
Net change	11,147	(48,369)
Cash and cash equivalents at beginning of period	60,691	102,309
Cash and cash equivalents at end of period	71,838	53,940
Parent
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	(74,500)	(90,400)
Additions to property and equipment	(4,700)	(5,800)
Principal receipts from long-term receivables	0	0
Proceeds from sale of assets	0	0
Other	0	0
Cash flows provided by (used in) investing activities	(4,700)	(5,800)
Revolving credit borrowings	50,000	25,000
Revolving credit repayments	(50,000)	(25,000)
Payment of debt	(184,200)	(153,400)
Payment of debt issuance costs	0	(12,300)
Purchase of common stock	0	(21,200)
Restricted cash	0	0
Other	7,400	6,200
Intercompany transfers	291,100	288,200
Cash flows provided by (used in) financing activities	114,200	107,500
Net change	35,100	11,300
Cash and cash equivalents at beginning of period	9,900	23,400
Cash and cash equivalents at end of period	45,000	34,700
Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	142,300	184,700
Additions to property and equipment	(8,800)	(15,000)
Principal receipts from long-term receivables	10,300	9,900
Proceeds from sale of assets	137,400	60,200
Other	1,000	(600)
Cash flows provided by (used in) investing activities	139,900	54,500
Revolving credit borrowings	0	0
Revolving credit repayments	0
Payment of debt	(8,200)	(10,300)
Payment of debt issuance costs	0	0
Purchase of common stock	0	0
Restricted cash	(8,200)	(1,600)
Other	1,200	400
Intercompany transfers	(291,100)	(286,400)
Cash flows provided by (used in) financing activities	(306,300)	(297,900)
Net change	(24,100)	(58,700)
Cash and cash equivalents at beginning of period	50,400	77,300
Cash and cash equivalents at end of period	26,200	18,600
Non-Guarantor Subsidiaries
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	200	800
Additions to property and equipment	0	0
Principal receipts from long-term receivables	0	0
Proceeds from sale of assets	0	0
Other	0	0
Cash flows provided by (used in) investing activities	0	0
Revolving credit borrowings	0	0
Revolving credit repayments	0
Payment of debt	0	0
Payment of debt issuance costs	0	0
Purchase of common stock	0	0
Restricted cash	0	0
Other	0	0
Intercompany transfers	0	(1,800)
Cash flows provided by (used in) financing activities	0	(1,800)
Net change	200	(1,000)
Cash and cash equivalents at beginning of period	400	1,600
Cash and cash equivalents at end of period	600	600
Consolidation, Eliminations
Condensed Financial Statements, Captions [Line Items]
Cash flows provided by (used in) operating activities	0	0
Additions to property and equipment		0
Principal receipts from long-term receivables	0	0
Proceeds from sale of assets	0	0
Other	0	0
Cash flows provided by (used in) investing activities	0	0
Revolving credit borrowings	0	0
Revolving credit repayments	0
Payment of debt	0	0
Payment of debt issuance costs	0	0
Purchase of common stock	0	0
Restricted cash	0	0
Other	0	0
Intercompany transfers	0	0
Cash flows provided by (used in) financing activities	0	0
Net change	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	$ 0	$ 0