Condensed Consolidated Statements Of Shareholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Common Stock Cumulative Effect, Period of Adoption	Common Stock	Retained Earnings Cumulative Effect, Period of Adoption	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Cumulative Effect, Period of Adoption	Total
Balance, beginning of period (Accounting Standards Update 2016-13) at Dec. 31, 2019			$ (620)			$ (620)
Balance, beginning of period at Dec. 31, 2019		$ 1,318,961		$ 445,370	$ (64,740)		$ 1,699,591
Balance, beginning of period (in shares) at Dec. 31, 2019		148,888
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)				18,011			18,011
Foreign currency translation adjustments					(16,057)		(16,057)
Unrealized gain on hedges, net of tax					285		285
Accretion of redeemable noncontrolling interests				(2,283)			(2,283)
Equity component of convertible senior notes		$ 33,336					33,336
Re-acquisition of equity component of convertible senior notes		(18,006)					(18,006)
Capped call transactions		(10,625)					(10,625)
Activity in company stock plans, net and other		$ (4,320)					(4,320)
Activity in company stock plans, net and other (in shares)		1,248
Share-based compensation		$ 6,174					6,174
Balance, end of period at Sep. 30, 2020		$ 1,325,520		460,478	(80,512)		1,705,486
Balance, end of period (in shares) at Sep. 30, 2020		150,136
Balance, beginning of period at Dec. 31, 2019							3,455
Increase (Decrease) in Redeemable Noncontrolling Interests [Roll Forward]
Net income (loss)							(2,044)
Foreign currency translation adjustments related to redeemable noncontrolling interests							(115)
Accretion of redeemable noncontrolling interests							2,283
Balance, end of period at Sep. 30, 2020							3,579
Balance, beginning of period at Jun. 30, 2020		$ 1,318,531		436,107	(99,938)		1,654,700
Balance, beginning of period (in shares) at Jun. 30, 2020		150,040
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)				24,499			24,499
Foreign currency translation adjustments					19,426		19,426
Accretion of redeemable noncontrolling interests				(128)			(128)
Equity component of convertible senior notes		$ 33,336					33,336
Re-acquisition of equity component of convertible senior notes		(18,006)					(18,006)
Capped call transactions		(10,625)					(10,625)
Activity in company stock plans, net and other		$ 193					193
Activity in company stock plans, net and other (in shares)		96
Share-based compensation		$ 2,091					2,091
Balance, end of period at Sep. 30, 2020		$ 1,325,520		460,478	(80,512)		1,705,486
Balance, end of period (in shares) at Sep. 30, 2020		150,136
Balance, beginning of period at Jun. 30, 2020							3,372
Increase (Decrease) in Redeemable Noncontrolling Interests [Roll Forward]
Net income (loss)							(54)
Foreign currency translation adjustments related to redeemable noncontrolling interests							133
Accretion of redeemable noncontrolling interests							128
Balance, end of period at Sep. 30, 2020							3,579
Balance, beginning of period (Accounting Standards Update 2020-06 [Member]) at Dec. 31, 2020	$ (41,456)		$ 6,682			$ (34,774)
Balance, beginning of period at Dec. 31, 2020		$ 1,327,592		464,524	(51,620)		1,740,496
Balance, beginning of period (in shares) at Dec. 31, 2020		150,341
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)				(35,630)			(35,630)
Foreign currency translation adjustments					(6,478)		(6,478)
Accretion of redeemable noncontrolling interests							(241)
Accretion of redeemable noncontrolling interests				1,489			1,489
Activity in company stock plans, net and other		$ (1,052)					(1,052)
Activity in company stock plans, net and other (in shares)		535
Share-based compensation		$ 5,613					5,613
Balance, end of period at Sep. 30, 2021		$ 1,290,697		437,065	(58,098)		1,669,664
Balance, end of period (in shares) at Sep. 30, 2021		150,876
Balance, beginning of period at Dec. 31, 2020							3,855
Increase (Decrease) in Redeemable Noncontrolling Interests [Roll Forward]
Net income (loss)							(146)
Foreign currency translation adjustments related to redeemable noncontrolling interests							48
Accretion of redeemable noncontrolling interests							(1,489)
Acquisition of redeemable noncontrolling interests							(2,268)
Balance, beginning of period at Jun. 30, 2021		$ 1,288,603		456,108	(44,651)		1,700,060
Balance, beginning of period (in shares) at Jun. 30, 2021		150,787
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)				(19,043)			(19,043)
Foreign currency translation adjustments					(13,447)		(13,447)
Activity in company stock plans, net and other		$ 262					262
Activity in company stock plans, net and other (in shares)		89
Share-based compensation		$ 1,832					1,832
Balance, end of period at Sep. 30, 2021		$ 1,290,697		$ 437,065	$ (58,098)		$ 1,669,664
Balance, end of period (in shares) at Sep. 30, 2021		150,876