Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid‑In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Beginning balance at Dec. 31, 2016	$ 1,204,307	$ 623	$ 731,562	$ 1,133,473	$ (70,300)	$ (591,051)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(84,850)			(84,850)
Currency translation adjustment (excluding intercompany advances)	11,316				11,316
Currency translation adjustment on intercompany advances	450				450
Other comprehensive income	41				41
Stock-based compensation expense:
Restricted stock	21,805	4	21,801
Stock options	1,244		1,244
Stock repurchases	(16,283)					(16,283)
Surrender of stock to settle taxes on restricted stock awards	(5,317)					(5,317)
Ending balance at Dec. 31, 2017	1,132,713	627	754,607	1,048,623	(58,493)	(612,651)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(19,105)			(19,105)
Currency translation adjustment (excluding intercompany advances)	(10,984)				(10,984)
Currency translation adjustment on intercompany advances	(2,104)				(2,104)
Other comprehensive income	184				184
Stock-based compensation expense:
Restricted stock	22,157	4	22,153
Stock options	492		492
Issuance of common stock in connection with GEODynamics Acquisition	294,910	87	294,823
Issuance of 1.50% convertible senior notes, net of income taxes of $7,744	25,683		25,683
Surrender of stock to settle taxes on restricted stock awards	(4,178)					(4,178)
Ending balance at Dec. 31, 2018	1,439,768	718	1,097,758	1,029,518	(71,397)	(616,829)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(231,808)			(231,808)
Currency translation adjustment (excluding intercompany advances)	3,925				3,925
Currency translation adjustment on intercompany advances	(463)				(463)
Other comprehensive income	189				189
Stock-based compensation expense:
Restricted stock	16,715	8	16,707
Stock options	53		53
Stock repurchases	(757)					(757)
Surrender of stock to settle taxes on restricted stock awards	(3,698)					(3,698)
Common stock withdrawn from deferred compensation plan	43		3			40
Ending balance at Dec. 31, 2019	$ 1,223,967	$ 726	$ 1,114,521	$ 797,710	$ (67,746)	$ (621,244)