Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Net income (loss)	$ (57,690)	$ (89,300)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	58,746	80,271
Allowance for doubtful accounts, net of recoveries	57	713
Loss (gain) on dispositions of property and equipment, net	(92)	(3,244)
Stock-based compensation expense	2,065	1,240
Amortization of debt issuance costs	844	827
Loss on extinguishment of debt	299	0
Impairment charges	0	77,319
Deferred income taxes	(4,348)	(8,267)
Change in other long-term assets	102	1,018
Change in other long-term liabilities	(1,063)	(1,606)
Changes in current assets and liabilities:
Receivables	24,159	91,881
Inventory	454	1,001
Prepaid expenses and other current assets	1,525	1,384
Accounts payable	(5,100)	(26,220)
Deferred revenues	(2,786)	22,798
Accrued expenses	(3,576)	(28,044)
Net cash provided by operating activities	13,596	121,771
Cash flows from investing activities:
Purchases of property and equipment	(13,240)	(84,027)
Proceeds from sale of property and equipment	812	34,538
Proceeds from insurance recoveries	0	227
Net cash used in investing activities	(12,428)	(49,262)
Cash flows from financing activities:
Debt repayments	0	(45,002)
Debt issuance costs	(809)	(5)
Proceeds from exercise of options	183	753
Purchase of treasury stock	(124)	(711)
Net cash used in financing activities	(750)	(44,965)
Net increase in cash and cash equivalents	418	27,544
Beginning cash and cash equivalents	14,160	34,924
Ending cash and cash equivalents	14,578	62,468
Supplementary disclosure:
Interest paid	12,053	11,385
Income tax paid	519	2,331
Noncash investing and financing activity:
Change in capital expenditure accruals	$ 722	$ 11,133