Pensions and Other Postretirement Benefits (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Defined Benefit Pension Plans [Member] | U.S. Plans [Member]
Components of net periodic pension cost [Abstract]
Net service cost	$ 0	$ 0	$ 0	$ 0
Interest cost	424	371	1,272	1,113
Expected return on plan assets	0	0	0	0
Amortization of prior service cost (credit)	36	36	108	108
Amortization of losses (gains)	118	159	354	477
Curtailment and settlement losses	0	0	0	0
Net periodic benefit cost	578	566	1,734	1,698
Defined Benefit Pension Plans [Member] | Non-U.S. Plans [Member]
Components of net periodic pension cost [Abstract]
Net service cost	841	900	2,538	2,775
Interest cost	1,271	1,175	3,843	3,628
Expected return on plan assets	(483)	(463)	(1,462)	(1,430)
Amortization of prior service cost (credit)	49	52	150	161
Amortization of losses (gains)	1,332	1,520	4,035	4,690
Curtailment and settlement losses	499	441	1,504	1,358
Net periodic benefit cost	3,509	3,625	10,608	11,182
Other Postretirement Benefits [Member] | U.S. Plans [Member]
Components of net periodic pension cost [Abstract]
Net service cost	36	35	106	103
Interest cost	77	69	232	205
Amortization of prior service cost (credit)	0	(37)	0	(111)
Amortization of losses (gains)	(32)	(10)	(96)	(29)
Net periodic benefit cost	81	57	242	168
Other Postretirement Benefits [Member] | Non-U.S. Plans [Member]
Components of net periodic pension cost [Abstract]
Net service cost	71	71	215	219
Interest cost	30	28	90	86
Amortization of prior service cost (credit)	0	0	0	0
Amortization of losses (gains)	27	26	81	80
Net periodic benefit cost	$ 128	$ 125	$ 386	$ 385