Significant Customers (Details) - U.S. Government - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2021	Jun. 28, 2020	Jun. 27, 2021	Jun. 28, 2020
Revenue, Major Customer [Line Items]
Sales to the U.S. Government, amount	$ 146.2	$ 129.4	$ 288.4	$ 253.5
Government contracts | Revenue
Revenue, Major Customer [Line Items]
Sales to the U.S. Government, percentage of total revenue (percent)	71.00%	76.00%	72.00%	75.00%