Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Offering costs, common stock issuance	$ 4,001
Cash flows from operating activities:
Net loss	(128,391)	$ (155,140)	$ (38,018)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	114,312	150,939	183,376
Provision for Doubtful Accounts	156	248	1,445
Write-off of obsolete inventory	101	0	331
Gain on dispositions of property and equipment, net	(1,892)	(4,344)	(1,859)
Stock-based compensation expense	3,944	3,629	7,617
Amortization of debt issuance costs, discount and premium	1,776	1,691	2,669
Gain on sale of fishing and rental services operations	0	0	(10,702)
Loss on extinguishment of debt	299	2,186	31,221
Impairment charges	12,815	129,152	73,025
Deferred income taxes	(11,608)	(39,286)	(14,761)
Change in other long-term assets	662	420	2,958
Change in other long-term liabilities	478	(132)	(1,352)
Changes in current assets and liabilities:
Receivables	16,341	114,644	(11,993)
Inventory	(630)	1,267	(1,068)
Prepaid expenses and other current assets	310	1,769	(55)
Accounts payable	1,969	(30,514)	7,167
Deferred revenues	(3,985)	1,922	2,616
Accrued expenses	(1,526)	(35,732)	424
Net cash provided by operating activities	5,131	142,719	233,041
Cash flows from investing activities:
Purchases of property and equipment	(32,381)	(159,615)	(175,378)
Proceeds from sale of fishing and rental services operations	0	0	15,090
Proceeds from sale of property and equipment	7,577	57,674	8,370
Proceeds from insurance recoveries	37	285	0
Net cash used in investing activities	(24,767)	(101,656)	(151,918)
Cash flows from financing activities:
Debt repayments	(71,000)	(60,002)	(490,025)
Proceeds from issuance of debt	22,000	0	440,000
Debt issuance costs	(819)	(1,877)	(9,239)
Tender premium costs	0	0	(21,553)
Proceeds from exercise of options	183	781	8,368
Proceeds from common stock, net of offering costs of $4,001	65,430	0	0
Purchase of treasury stock	(124)	(729)	(1,135)
Net cash provided by (used in) financing activities	15,670	(61,827)	(73,584)
Net increase (decrease) in cash and cash equivalents	(3,966)	(20,764)	7,539
Beginning cash and cash equivalents	14,160	34,924	27,385
Ending cash and cash equivalents	10,194	14,160	34,924
Supplementary disclosure:
Interest paid	24,516	22,506	43,690
Income tax paid	671	2,691	5,012
Noncash investing and financing activity:
Change in capital expenditure accruals	$ 175	$ (16,708)	$ 12,743