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Restructuring, Impairment and Other Charges (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
	Apr. 30, 2019	Dec. 26, 2020	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Restructuring Cost and Reserve
Restructuring charges										$ 5,638	$ 12,711	$ 10,365
Impairment			$ 100			$ 4,200		$ 200	$ 2,800	36,078	322	2,218
Total		$ 800	1,300	$ 1,800		2,100	$ 2,500	5,700		41,716	13,033	12,583
Acquisition related costs		700	$ 300	100	$ 1,200	1,900	$ 3,200	$ 1,500	$ 2,400
Restructuring reserves		$ 4,200				$ 2,700				4,200	2,700
Employee terminations
Restructuring Cost and Reserve
Restructuring charges	$ 1,700									5,453	10,359	9,503
Other restructuring charges
Restructuring Cost and Reserve
Restructuring charges	$ 1,400									185	2,352	862
Electronics
Restructuring Cost and Reserve
Restructuring charges										2,540	5,501	9,412
Impairment										0	0	0
Total										2,540	5,501	9,412
Electronics \| Employee terminations
Restructuring Cost and Reserve
Restructuring charges										2,540	5,313	8,742
Electronics \| Other restructuring charges
Restructuring Cost and Reserve
Restructuring charges										0	188	670
Automotive
Restructuring Cost and Reserve
Restructuring charges										857	5,965	826
Impairment										33,841	322	88
Total										34,698	6,287	914
Automotive \| Employee terminations
Restructuring Cost and Reserve
Restructuring charges										682	4,251	634
Automotive \| Other restructuring charges
Restructuring Cost and Reserve
Restructuring charges										175	1,714	192
Industrial
Restructuring Cost and Reserve
Restructuring charges										2,241	1,245	127
Impairment				$ 2,200						2,237	0	2,130
Total										4,478	1,245	2,257
Industrial \| Employee terminations
Restructuring Cost and Reserve
Restructuring charges										2,231	795	127
Industrial \| Other restructuring charges
Restructuring Cost and Reserve
Restructuring charges										$ 10	$ 450	$ 0