Industry Segments - Revenue by type of service (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) category	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Revenue from External Customer
Number of Revenue Categories by Type of Service | category									2
Revenue	$ 13,962	$ 31,242	$ 30,722	$ 24,326	$ 52,351	$ 41,299	$ 47,334	$ 57,053	$ 100,252	$ 198,037	$ 202,874
Acquisition and licensing of seismic data [Member]
Revenue from External Customer
Revenue									97,938	194,037	198,109
Reproduction and delivery of seismic data and other services [Member]
Revenue from External Customer
Revenue									$ 2,314	$ 4,000	$ 4,765