Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 83,282	$ 42,402
Short-term investments		20,000
Accounts receivable, net	68,693	130,612
Unbilled receivables	57,928	25,628
Inventories	69,502	70,145
Prepaid expenses and other current assets	19,655	13,460
Total current assets	299,060	302,247
Deferred income tax asset	19,722	17,645
Property, plant, equipment and seismic rental equipment, net	34,823	24,771
Multi-client data library, net	187,431	175,768
Investment in INOVA Geophysical	79,587	72,626
Goodwill	54,399	53,963
Intangible assets, net	16,795	17,716
Other assets	10,237	9,322
Total assets	702,054	674,058
Current liabilities:
Current maturities of long-term debt	2,817	5,770
Accounts payable	25,842	22,296
Accrued expenses	67,723	61,384
Accrued multi-client data library royalties	15,602	15,318
Deferred revenue	27,626	33,802
Total current liabilities	139,610	138,570
Long-term debt, net of current maturities	102,166	99,342
Other long-term liabilities	7,574	7,719
Total liabilities	249,350	245,631
Redeemable noncontrolling interest	2,204	2,615
Equity:
Cumulative convertible preferred stock	27,000	27,000
Common stock, $0.01 par value; authorized 200,000,000 shares; outstanding 155,846,861 and 155,479,776 shares at June 30, 2012 and December 31, 2011, respectively, net of treasury stock	1,558	1,555
Additional paid-in capital	845,477	843,271
Accumulated deficit	(402,660)	(423,612)
Accumulated other comprehensive loss	(14,776)	(16,193)
Treasury stock, at cost, 849,539 shares at June 30, 2012 and December 31, 2011, respectively	(6,565)	(6,565)
Total stockholders' equity	450,034	425,456
Noncontrolling interests	466	356
Total equity	450,500	425,812
Total liabilities and equity	$ 702,054	$ 674,058