Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income (loss)	$ (202,979)	$ (215,235)	$ 62,375
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	58,182	72,591	75,336
Amortization of deferred financing costs	3,254	2,394	1,945
Amortization of stock-based compensation	5,209	6,735	7,330
Provision for doubtful accounts receivable, net of write offs	1,801	(862)	3,236
Deferred income tax benefit	(38,456)	(3,823)	(66)
(Gain) loss on sale of assets	8,564	1,160	(12,461)
Asset Impairment Charges	162,808	152,103	8,995
Gain on extinguishment of debt	(35,912)	(458)
Other financing costs	5,988
Foreign currency (gain) loss	1,025	(160)	1,490
Change in operating assets and liabilities —
Accounts receivable	15,144	47,317	5,700
Prepaids and other	1,677	214	(476)
Accounts payable	(593)	(8,602)	(3,888)
Other accrued liabilities and other	(9,051)	(10,056)	4,332
Net cash (used in) provided by operating activities	(23,339)	43,357	153,848
Cash flows from investing activities:
Purchases of vessels, equipment and other fixed assets	(16,188)	(35,428)	(158,425)
Release of deposits held in escrow		3,683	5,060
Proceeds from disposition of vessels, equipment and other fixed assets	6,529	8,910	32,261
Net cash used in investing activities	(9,659)	(22,835)	(121,104)
Cash flows from financing activities:
Repuchase of 6.375% senior notes	(33,448)	(542)
Repayment of revolving loan facility	(5,000)	(91,000)
Borrowings under revolving loan facility, net	65,194	47,000	47,167
Cash dividends			(26,152)
Stock repurchases			(57,887)
Debt issuance costs	(971)	(3,566)	(4,198)
Other financing costs	(5,988)
Proceeds from issuance of stock	380	827	1,046
Net cash provided by (used in) financing activities	20,167	(47,281)	(40,024)
Effect of exchange rate changes on cash	(286)	(2,087)	(2,501)
Net decrease in cash and cash equivalents	(13,117)	(28,846)	(9,781)
Cash and cash equivalents at beginning of year	21,939	50,785	60,566
Cash and cash equivalents at end of year	8,822	21,939	50,785
Supplemental cash flow information:
Interest paid, net of interest capitalized	30,820	29,834	27,067
Income taxes paid, net	$ 2,124	$ 2,048	$ 4,454