CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands		Total	Common Stock Issued	Additional Paid–In Capital	Accumulated Other Comprehensive Loss	Treasury Stock	Retained Earnings	Non–Controlling Interest
Beginning Balance (in shares) at Dec. 31, 2018			47,557
Beginning balance at Dec. 31, 2018		$ 1,795,924	$ 475	$ 593,262	$ (117,291)	$ (172,342)	$ 1,481,593	$ 10,227
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued (in shares)			117
Stock issued		405	$ 1	404
Share repurchases for tax withholdings		(9,723)		(9,723)
Stock-based compensation expense		9,703		9,703
Adjustments of redeemable non-controlling interest		0		41,400			(41,400)
Foreign currency translation		4,371			4,409			(38)
Net (loss) income		16,208					16,134	74
Ending Balance (in shares) at Mar. 31, 2019			47,674
Ending balance at Mar. 31, 2019		1,816,888	$ 476	635,046	(112,882)	(172,342)	1,456,327	10,263
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative-effect adjustment	[1]	(8,777)					(8,587)	(190)
Beginning balances, adjusted		1,927,745	$ 477	675,060	(115,449)	(172,342)	1,530,614	9,385
Beginning Balance (in shares) at Dec. 31, 2019			47,749
Beginning balance at Dec. 31, 2019		1,936,522	$ 477	675,060	(115,449)	(172,342)	1,539,201	9,575
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued (in shares)			189
Stock issued		1,952	$ 2	1,950
Share repurchases for tax withholdings		(8,817)		(8,817)
Stock-based compensation expense		12,533		12,533
Accretion of redeemable non-controlling interest		(2,624)					(2,624)
Foreign currency translation		(41,404)			(40,935)			(469)
Net (loss) income		(12,411)					(13,632)	1,221
Ending Balance (in shares) at Mar. 31, 2020			47,938
Ending balance at Mar. 31, 2020		$ 1,876,974	$ 479	$ 680,726	$ (156,384)	$ (172,342)	$ 1,514,358	$ 10,137

[1] the impact of the Company’s modified retrospective adoption of ASU 2016-13 (See Note 2, Recent Accounting Pronouncements).