Restructuring and Contract Termination Charges, Net (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 29, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Jan. 02, 2022	Jan. 03, 2021	Dec. 29, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net					$ 16,432	$ 8,013	$ 29,428
Restructuring Reserve1					10,300	8,300
Short-term accrued restructuring and other costs [Member]
Restructuring Cost and Reserve [Line Items]
Accrued restructuring and contract termination costs						4,700
Accrued expenses and other current liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Accrued restructuring and contract termination costs					8,000	2,000
Long-term liabilities [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Noncurrent					700
Operating lease right-of-use assets [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve, Noncurrent					1,600	1,600
Q1 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net				$ 7,460
Q2 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net			$ 5,590
Q3 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net		$ 13,797
Q4 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net	$ 2,581
Facility Relocation [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges and Changes in Estimates					$ 7,100	4,300	800
Discovery & Analytical Solutions [Member] | Contract Termination [Member] | 2020 Contract Termination Charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net						200
Discovery & Analytical Solutions [Member] | Contract Termination [Member] | 2019 Contract Termination Charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net							200
Discovery & Analytical Solutions [Member] | Severance [Member] | Q1 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net				6,001
Discovery & Analytical Solutions [Member] | Severance [Member] | Q2 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net			4,461
Discovery & Analytical Solutions [Member] | Severance [Member] | Q3 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net		11,156
Discovery & Analytical Solutions [Member] | Severance [Member] | Q4 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net	177
Diagnostics [Member] | Contract Termination [Member] | 2020 Contract Termination Charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net						$ 100	$ 200
Diagnostics [Member] | Severance [Member] | Q1 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net				$ 1,459
Diagnostics [Member] | Severance [Member] | Q2 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net			$ 1,129
Diagnostics [Member] | Severance [Member] | Q3 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net		$ 2,641
Diagnostics [Member] | Severance [Member] | Q4 2019 Restructuring Plan [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and other costs, net	$ 2,404