Restructuring - Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 29, 2020	Mar. 31, 2019
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	$ 1,576	$ (665)
Cumulative To Date	404,840
December 2019 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	1,639	0
Cumulative To Date	9,035
February 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	2	(576)
Cumulative To Date	19,041
Legacy Restructuring Plans
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	(65)	(89)
Cumulative To Date	376,764
Non-cash impairment charges | February 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	0	0
Cumulative To Date	5,874
Non-cash impairment charges | Legacy Restructuring Plans
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	0	0
Cumulative To Date	228,184
Severance and benefits | December 2019 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	1,639	0
Cumulative To Date	8,994
Severance and benefits | February 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	0	(349)
Cumulative To Date	11,797
Severance and benefits | Legacy Restructuring Plans
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	(65)	(17)
Cumulative To Date	100,688
Lease and related termination costs | February 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	0	0
Cumulative To Date	554
Lease and related termination costs | Legacy Restructuring Plans
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	0	0
Cumulative To Date	8,085
Other costs1 | December 2019 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	0	0
Cumulative To Date	41
Other costs1 | February 2018 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	2	(227)
Cumulative To Date	816
Other costs1 | Legacy Restructuring Plans
Restructuring Cost and Reserve [Line Items]
Business reorganization costs	0	$ (72)
Cumulative To Date	$ 39,807