Segment and Geographic Information - Depreciation and Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	$ 63,694	$ 55,310	$ 62,311
Operating segments | E&P Technology & Services
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	53,663	44,100	51,014
Operating segments | E&P Operations Optimization
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	1,349	1,780	2,869
Operating segments | Ocean Bottom Seismic Services
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	7,001	7,511	6,158
Support and other
Segment Reporting Information [Line Items]
Depreciation and amortization (including multi-client data library)	$ 1,681	$ 1,919	$ 2,270