Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 88,239	$ 173,608	$ 129,847	$ 148,056
Accounts receivable, net	21,587	114,325
Unbilled receivables	32,387	22,599
Inventories	34,683	51,162
Prepaid expenses and other current assets	10,124	13,662
Total current assets	187,020	375,356
Deferred income tax asset	5,706	8,604
Property, plant, equipment and seismic rental equipment, net	77,081	69,840
Multi-client data library, net	135,907	118,669
Goodwill	26,809	27,388
Intangible assets, net	5,306	6,788
Other assets	9,380	10,612
Total assets	447,209	617,257
Current liabilities:
Current maturities of long-term debt	6,612	7,649
Accounts payable	27,950	36,863
Accrued expenses	54,302	65,264
Accrued multi-client data library royalties	12,443	35,219
Deferred revenue	5,575	8,262
Total current liabilities	106,882	153,257
Long-term debt, net of current maturities	179,666	182,945
Other long-term liabilities	39,830	143,804
Total liabilities	326,378	480,006
Redeemable noncontrolling interest	1,200	1,539
Equity:
Common stock, $0.01 par value; authorized 200,000,000 shares; outstanding 164,790,322 and 164,484,095 shares at September 30, 2015 and December 31, 2014, respectively, net of treasury stock	1,648	1,645
Additional paid-in capital	892,007	887,749
Accumulated deficit	(753,987)	(734,409)
Accumulated other comprehensive loss	(13,564)	(12,807)
Treasury stock, at cost, 849,539 shares	(6,565)	(6,565)
Total stockholders' equity	119,539	135,613
Noncontrolling interest	92	99
Total equity	119,631	135,712
Total liabilities and equity	$ 447,209	$ 617,257