Consolidated Condensed Statements of Shareholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Balance at period start (in shares) at Dec. 31, 2023		31,299
Accumulated Other Comprehensive Income (Loss), Net of Tax at Dec. 31, 2023	$ 834,222	$ 313	$ 446,535	$ 452,531	$ (50,170)	$ (14,987)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee plans	282		(562)			844
Stock-based compensation	6,240		6,240
Dividends on common stock ($0.20 per share)	(6,158)			(6,158)
Settlement of convertible notes hedge transactions	0		10,980			(10,980)
Shares issued for the settlement of convertible notes	0		(5,169)			5,169
Comprehensive income:
Cash flow hedging gain (loss), net of income tax	4,448				4,448
Pension liability, net of income tax	301				301
Foreign currency translation adjustments	(4,380)				(4,380)
Net income	19,709			19,709
Comprehensive income	20,078
Balance at period end (in shares) at Mar. 31, 2024		31,299
Accumulated Other Comprehensive Income (Loss), Net of Tax at Mar. 31, 2024	854,664	$ 313	458,024	466,082	(49,801)	(19,954)
Balance at period start (in shares) at Dec. 31, 2024		31,299
Accumulated Other Comprehensive Income (Loss), Net of Tax at Dec. 31, 2024	962,681	$ 313	476,575	560,277	(58,857)	(15,627)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued under employee plans	(223)		(1,340)			1,117
Stock-based compensation	13,863		13,863
Dividends on common stock ($0.20 per share)	(6,186)			(6,186)
Comprehensive income:
Cash flow hedging gain (loss), net of income tax	(3,669)				(3,669)
Pension liability, net of income tax	268				268
Foreign currency translation adjustments	4,866				4,866
Net income	6,036			6,036
Comprehensive income	7,501
Balance at period end (in shares) at Mar. 31, 2025		31,299
Accumulated Other Comprehensive Income (Loss), Net of Tax at Mar. 31, 2025	$ 977,636	$ 313	$ 489,098	$ 560,127	$ (57,392)	$ (14,510)