Reorganization and Realignment Costs G&A Realignment Accrual Rollforward (Details) - G&A Realignment - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Restructuring Cost and Reserve
Beginning balance			$ 5,359	$ 7,324
Charges	$ (6)	$ 2,683	162	3,285
Payments			(2,708)	(5,167)
Ending balance	2,813	5,442	2,813	5,442
Severance and related employee costs
Restructuring Cost and Reserve
Beginning balance			5,276	7,241
Charges	(6)	2,130	146	2,602
Payments			(2,671)	(4,724)
Ending balance	2,751	5,119	2,751	5,119
Recruitment and relocation
Restructuring Cost and Reserve
Beginning balance			83	83
Charges	0	482	15	596
Payments			(36)	(356)
Ending balance	62	323	62	323
Third-party and other costs
Restructuring Cost and Reserve
Beginning balance			0	0
Charges	0	71	1	87
Payments			(1)	(87)
Ending balance	0	0	0	0
Accrued expenses and other current liabilities
Restructuring Cost and Reserve
Ending balance	2,705	4,835	2,705	4,835
Other Liabilities
Restructuring Cost and Reserve
Ending balance	$ 108	$ 607	$ 108	$ 607