Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities:
Net income	$ 256	$ 78,932
Adjustments to reconcile net income to cash (used in) provided by operating activities:
Depreciation and amortization (other than multi-client data library)	13,015	13,785
Amortization of multi-client data library	10,440	34,257
Stock-based compensation expense	3,047	5,033
Reductions of accrual for loss contingency related to legal proceedings	(101,978)	(69,557)
Equity in losses of investments	0	3,469
Gain on sale of Source product line	0	(6,522)
Deferred income taxes	(24)	(5,612)
Change in operating assets and liabilities:
Accounts receivable	87,796	73,254
Unbilled receivables	9,198	(14,236)
Inventories	(739)	(3,197)
Accounts payable, accrued expenses and accrued royalties	(40,649)	(30,807)
Deferred revenue	2,405	(4,988)
Other assets and liabilities	(5,262)	2,927
Net cash (used in) provided by operating activities	(22,495)	76,738
Cash flows from investing activities:
Cash invested in multi-client data library	(13,598)	(34,317)
Purchase of property, plant, equipment and seismic rental assets	(17,213)	(4,543)
Repayment of advance to INOVA Geophysical	0	1,000
Net investment in and advances to OceanGeo B.V. prior to its consolidation	0	(3,074)
Net proceeds from sale of Source product line	0	14,394
Other investing activities	257	605
Net cash used in investing activities	(30,554)	(25,935)
Cash flows from financing activities:
Borrowings under revolving line of credit	0	15,000
Payments under revolving line of credit	0	(50,000)
Payments on notes payable and long-term debt	(3,560)	(5,595)
Other financing activities	22	(339)
Net cash used in financing activities	(3,538)	(40,934)
Effect of change in foreign currency exchange rates on cash and cash equivalents	39	(146)
Net (decrease) increase in cash and cash equivalents	(56,548)	9,723
Cash and cash equivalents at beginning of period	173,608	148,056
Cash and cash equivalents at end of period	$ 117,060	$ 157,779