Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Net income (loss)	$ (60,299)	$ 256
Adjustments to reconcile net income (loss) to cash used in operating activities:
Depreciation and amortization (other than multi-client data library)	11,416	13,015
Amortization of multi-client data library	14,244	10,440
Stock-based compensation expense	1,610	3,047
Reduction of accrual for loss contingency related to legal proceedings	0	(101,978)
Loss on extinguishment of debt	2,182	0
Deferred income taxes	381	(24)
Change in operating assets and liabilities:
Accounts receivable	23,980	87,796
Unbilled receivables	(2,042)	9,198
Inventories	1,329	(739)
Accounts payable, accrued expenses and accrued royalties	(5,518)	(40,649)
Deferred revenue	1,151	2,405
Other assets and liabilities	(773)	(5,262)
Net cash used in operating activities	(12,339)	(22,495)
Cash flows from investing activities:
Cash invested in multi-client data library	(8,648)	(13,598)
Purchase of property, plant, equipment and seismic rental assets	(340)	(17,213)
Other investing activities	0	257
Net cash used in investing activities	(8,988)	(30,554)
Cash flows from financing activities:
Borrowings under revolving line of credit	15,000	0
Repurchase of common stock	(964)	0
Payments on notes payable and long-term debt	(4,786)	(3,560)
Costs associated with issuance of debt	(6,174)	0
Payment to repurchase bonds	(15,000)	0
Other financing activities	13	22
Net cash used in financing activities	(11,911)	(3,538)
Effect of change in foreign currency exchange rates on cash and cash equivalents	738	39
Net decrease in cash and cash equivalents	(32,500)	(56,548)
Cash and cash equivalents at beginning of period	84,933	173,608
Cash and cash equivalents at end of period	$ 52,433	$ 117,060