Pensions and Other Postretirement Benefits (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2017	Jul. 02, 2016	Jul. 01, 2017	Jul. 02, 2016
Non-U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost	$ 925	$ 791	$ 1,828	$ 1,565
Interest cost	1,199	1,383	2,366	2,736
Expected return on plan assets	(518)	(542)	(1,024)	(1,076)
Amortization of prior service cost (credit)	18	13	36	25
Amortization of losses (gains)	1,523	1,201	3,001	2,372
Curtailments and settlements	330	201	652	396
Net periodic benefit cost	3,477	3,047	6,859	6,018
U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost	0	0	0	0
Interest cost	411	2,889	821	5,889
Expected return on plan assets	0	(2,826)	0	(5,651)
Amortization of prior service cost (credit)	36	36	72	72
Amortization of losses (gains)	83	1,651	165	3,301
Curtailments and settlements	0	0	0	0
Net periodic benefit cost	530	1,750	1,058	3,611
U.S. Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost	33	32	66	63
Interest cost	78	85	155	170
Amortization of prior service cost (credit)	(209)	(209)	(418)	(418)
Amortization of losses (gains)	(23)	(7)	(46)	(15)
Net periodic benefit cost	(121)	(99)	(243)	(200)
Non-U.S. Other Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net service cost	67	68	131	135
Interest cost	26	36	50	72
Amortization of prior service cost (credit)	0	0	0	0
Amortization of losses (gains)	15	17	29	34
Net periodic benefit cost	108	$ 121	$ 210	$ 241
Republic of China (Taiwan) [Member] | Non-U.S. Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Company pension contributions	$ 4,409