Consolidated Statements of Stockholders' Equity - 3 months ended Mar. 31, 2020 - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at at Dec. 31, 2019	$ 460,342	$ 593	$ 475,720	$ 45,895	$ (61,866)
Balance at (in shares) at Dec. 31, 2019		59,329,431
Stock-based compensation plans
Stock Issued During Period, Value, Restricted Stock Award, Gross	0	$ 2	(2)
Grant of restricted stock (in shares)		200,500
Issuance of common shares, net of withholdings	(1,115)	$ 1	(1,116)
Issuance of common shares, net of withholdings (in shares)		93,264
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	1,821		1,821
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	138,255			137,505
Balance at at Mar. 31, 2020	$ 599,303	$ 596	$ 476,423	$ 183,400	$ (61,116)
Balance at (in shares) at Mar. 31, 2020		59,623,195