Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Operating activities:
Net loss	$ (9,043)	$ (645)
Adjustments to reconcile net loss to net cash provided by operating activities:
Provision for doubtful accounts	1,577	1,338
Share-based payment	735	42
Depreciation and amortization	39,543	50,139
Amortization of deferred financing costs	2,051	1,934
Accretion of discount on long-term debt	754	842
Adjustment of derivatives to fair value	340	(67)
Distributions (less) more than undistributed earnings from investees	(19)	(149)
Deferred income taxes	(7,341)	(5,256)
Loss (gain) on sale of assets	(1,109)	895
Loss on extinguishment of debt	17,069	0
Impairment of assets held for sale	4,867	0
Changes in operating assets and liabilities, net of the effects of acquisitions:
Accounts receivable	(3,067)	1,486
Prepaid expenses	(2,378)	939
Other receivables	(337)	(796)
Other assets	172	(1,873)
Accounts payable	(1,885)	(4,672)
Accrued compensation and related expenses	(3,512)	794
Accrued interest payable	(2,574)	(321)
Income taxes payable	0	23
Other accrued liabilities	(3,330)	(1,887)
Net cash provided by operating activities	32,513	42,766
Investing activities:
Equipment purchases	(10,357)	(9,927)
(Increase) decrease in deposits on equipment	3,884	(5,531)
Decrease in cash in escrow	0	1,257
Proceeds from sale of assets	2,258	4,500
Net cash used in investing activities	(4,215)	(9,701)
Financing activities:
Principal payments on equipment debt	(7,269)	(6,337)
Proceeds from equipment debt	4,845	854
Proceeds from term loan facility	337,900	0
Principal payments on term loan facility	(340,435)	(6,000)
Payments of debt issuance costs	(9,494)	(200)
Noncontrolling interest in subsidiaries	(6,848)	(3,696)
Proceeds from shared-based payment arrangements	29	0
Purchase of treasury stock	0	(10)
Net cash used in financing activities	(21,272)	(15,389)
Net increase in cash and cash equivalents	7,026	17,676
Cash and cash equivalents, beginning of period	39,977	44,190
Cash and cash equivalents, end of period	47,003	61,866
Supplemental disclosure of cash flow information:
Interest paid	23,528	25,012
Income taxes paid, net of refunds	1,927	523
Supplemental disclosure of non-cash investing and financing activities:
Net book value of assets exchanged	0	4,467
Capital lease obligations related to the purchase of equipment	0	4,017
Comprehensive gain (loss) from hedging transactions, net of taxes	(272)	92
Equipment purchases in accounts payable	$ 634	$ 1,784