Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net loss	$ (241,745)	$ (8,341)	$ (35,929)
Adjustments to reconcile net loss to net cash provided by operating activities
Depreciation and amortization	241,471	217,480	209,747
Goodwill impairment	81,877	34,703
Accretion on asset retirement obligation	134	132	112
Change in allowance for doubtful accounts	638	(1,643)	895
Amortization of deferred financing costs	3,622	3,176	3,102
Amortization of premium on notes	(261)	(242)	(224)
Non-cash compensation	13,728	14,714	11,830
Loss on disposal of assets	1,602	1,974	2,873
Deferred income taxes	(131,171)	87	(20,030)
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable	144,430	(41,143)	3,813
Inventories	7,846	(9,798)	5,990
Prepaid expenses and other current assets	(740)	(14,435)	(1,046)
Other assets	(767)	(1,810)	(1,154)
Accounts payable	3,903	5,110	(16,232)
Income tax receivable	1,293	(204)	(922)
Other liabilities	1,109	11,303	6,767
Accrued expenses	(31,430)	13,473	(4,004)
Net cash provided by operating activities	95,539	224,536	165,588
Cash flows from investing activities:
Purchase of property and equipment	(53,868)	(236,295)	(136,950)
Proceeds from sale of assets	8,109	39,835	19,863
Payments for other long-term assets		(879)	(1,132)
Payments for businesses, net of cash acquired	(16,730)	(16,090)	(21,467)
Net cash used in investing activities	(62,489)	(213,429)	(139,686)
Cash flows from financing activities:
Proceeds from debt	8,816	16,000
Payments of debt	(68,635)	(47,894)	(45,397)
Purchase of treasury stock	(5,742)	(12,733)	(3,605)
Tax withholding from exercise of stock options	(3)	(362)	(200)
Exercise of employee stock options	727	4,646	781
Deferred loan costs and other financing activities	(1,396)	(2,381)	(514)
Net cash used in financing activities	(66,233)	(42,724)	(48,935)
Net decrease in cash and equivalents	(33,183)	(31,617)	(23,033)
Cash and cash equivalents - beginning of year	79,915	111,532	134,565
Cash and cash equivalents - end of year	$ 46,732	$ 79,915	$ 111,532