Supplemental Cash Flow Information and Non-cash Activity (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash paid during the period for:
Interest		$ 14,181	$ 15,691	$ 15,441
Income taxes		7,030	4,474	8,163
Non-cash items from investing and financing activities:
Purchase of computer equipment financed through capital leases		0	0	1,178
Leasehold improvement paid by landlord		0	955	0
Issuance of stock in bond exchange		0	10,741	0
Investment in multi-client data library financed through trade payables		9,059	0	8,939
Segment Reporting Information [Line Items]
Transfer of inventory to property, plant and equipment		0	17,662	15,936
Purchase of property, plant, equipment and seismic rental equipment		$ 1,063	$ 1,488	19,241
Ocean Bottom Seismic Services
Segment Reporting Information [Line Items]
Transfer of inventory to property, plant and equipment	$ 17,700
Purchase of property, plant, equipment and seismic rental equipment				$ 15,300