Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balance, shares at Dec. 31, 2015		109,442,000
Beginning balance at Dec. 31, 2015	$ 383,590	$ 1,094	$ 818,339	$ 922,878	$ (1,347,677)	$ (11,044)
Net earnings (loss)	(105,195)			(105,195)
Foreign currency translation adjustments, net of tax ($73), $2,822, and ($2,794) for 2018, 2017, and 2016, respectively	(5,188)
Total other comprehensive income (loss)	(5,188)					(5,188)
Vesting of restricted share units, shares		77,000
Vesting of restricted share units	0	$ 1	(1)
Tax effect of stock awards vested and options exercised	(440)		(440)
Stock-based compensation expense	9,209		(9,209)
Dividends declared	(17,043)			(17,043)
Ending balance, shares at Dec. 31, 2016		109,519,000
Ending balance at Dec. 31, 2016	264,933	$ 1,095	827,107	800,640	(1,347,677)	(16,232)
Net earnings (loss)	6,653			6,653
Foreign currency translation adjustments, net of tax ($73), $2,822, and ($2,794) for 2018, 2017, and 2016, respectively	5,241
Total other comprehensive income (loss)	5,241					5,241
Exercise of stock options, shares		27,000
Exercise of stock options	270		270
Vesting of restricted share units, shares		136,000
Vesting of restricted share units	0	$ 2	(2)
Stock-based compensation expense	3,896		(3,896)
Dividends declared	(8,550)			(8,550)
Ending balance, shares at Dec. 31, 2017		109,682,000
Ending balance at Dec. 31, 2017	272,443	$ 1,097	831,271	798,743	(1,347,677)	(10,991)
Net earnings (loss)	8,492			8,492
Foreign currency translation adjustments, net of tax ($73), $2,822, and ($2,794) for 2018, 2017, and 2016, respectively	(274)
Total other comprehensive income (loss)	$ (274)
Exercise of stock options, shares	137,509	138,000
Exercise of stock options	$ 1,400	$ 1	1,399
Vesting of restricted share units, shares		90,000
Vesting of restricted share units	0	$ 1	(1)
Tax effect of stock awards vested and options exercised	(194)		(194)
Stock-based compensation expense	5,961		5,961
Ending balance, shares at Dec. 31, 2018		109,910,000
Ending balance at Dec. 31, 2018	286,517	$ 1,099	$ 838,436	805,924	$ (1,347,677)	$ (11,265)
ASC 606 adoption	$ (1,311)			$ (1,311)