Supplemental Cash Flow Information and Non-Cash Activity (Tables)

3 Months Ended

Mar. 31, 2014

Supplemental Cash Flow Elements [Abstract]

Summary of Non-cash Items from Investing and Financing Activities

A summary of non-cash items from investing and financing activities is as follows (in thousands):

	Three Months Ended March 31,
	2014		2013
Purchases of computer equipment financed through capital leases	$	1,952	$	—
Transfer of inventory to property, plant, equipment and seismic rental equipment	$	2,308	$	134