Shareholders' Equity - Activity in Shareholders' Equity (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jul. 01, 2018	Mar. 31, 2018	Sep. 29, 2019	Sep. 30, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance			$ 354,663				$ 354,663
Net income	$ 26,210			$ 8,172			62,768	$ 43,858
Share repurchases		$ (25,200)
Pension liability adjustment	1,076			(196)			1,814	1,047
Foreign currency translation adjustment	(18,585)			4,964			(19,539)	(6,979)
Cash flow hedge unrealized gain (loss)	(941)			$ 286			(8,914)	$ 2,565
Balance	$ 357,378						$ 357,378
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance (in shares)	58,433	60,016	59,508	59,493	59,498	59,806	59,508	59,806
Balance	$ 5,843	$ 6,002	$ 5,951	$ 5,949	$ 5,950	$ 5,981	$ 5,951	$ 5,981
Stock issuances under employee plans (shares)		2	509	10	4	175
Stock issuances under employee plans			$ 51	$ 1		$ 17
Other issuances of common stock (in shares)		(1)	224	2		187
Other issuances of common stock			$ 22	$ 1		$ 19
Forfeitures and compensation expense related to stock awards (in shares)		(28)	(225)		(9)	(55)
Forfeitures and compensation expense related to stock awards		$ (3)	$ (22)		$ (1)	$ (6)
Share repurchases (in shares)		(1,556)				(615)
Share repurchases		$ (156)				$ (61)
Balance (in shares)	58,433	58,433	60,016	59,505	59,493	59,498	58,433	59,505
Balance	$ 5,843	$ 5,843	$ 6,002	$ 5,951	$ 5,949	$ 5,950	$ 5,843	$ 5,951
ADDITIONAL PAID-IN CAPITAL
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	247,221	270,655	270,269	262,285	260,115	271,271	270,269	271,271
Stock issuances under employee plans		6	379	86	35	102
Other issuances of common stock			3,900	40		4,769
Unamortized stock compensation expense related to restricted stock awards		52	(3,922)	(40)		(4,788)
Forfeitures and compensation expense related to stock awards	1,303	1,506	29	2,929	2,135	3,185
Share repurchases		(24,998)				(14,424)
Balance	248,524	247,221	270,655	265,300	262,285	260,115	248,524	265,300
RETAINED EARNINGS
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	251,009	225,373	222,214	215,383	198,649	187,433	222,214	187,433
Net income	26,210	29,499	7,059	8,172	20,602	15,084
Cash dividends paid	(3,798)	(3,863)	(3,900)	(3,866)	(3,868)	(3,868)
Balance	273,421	251,009	225,373	219,689	215,383	198,649	273,421	219,689
PENSION LIABILITY
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	(42,872)	(43,701)	(43,610)	(55,311)	(58,770)	(56,554)	(43,610)	(56,554)
Pension liability adjustment	1,076	829	(91)	(196)	3,459	(2,216)
Balance	(41,796)	(42,872)	(43,701)	(55,507)	(55,311)	(58,770)	(41,796)	(55,507)
FOREIGN CURRENCY TRANSLATION ADJUSTMENT
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	(102,441)	(106,690)	(101,487)	(90,886)	(70,113)	(78,943)	(101,487)	(78,943)
Foreign currency translation adjustment	(18,585)	4,249	(5,203)	4,964	(20,773)	8,830
Balance	(121,026)	(102,441)	(106,690)	(85,922)	(90,886)	(70,113)	(121,026)	(85,922)
CASH FLOW HEDGE
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance	(6,647)	(1,980)	1,326	3,183	2,536	904	1,326	904
Cash flow hedge unrealized gain (loss)	(941)	(4,667)	(3,306)	286	647	1,632
Balance	$ (7,588)	$ (6,647)	$ (1,980)	$ 3,469	$ 3,183	$ 2,536	$ (7,588)	$ 3,469