Debt - Effect of Derivatives on Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020
Debt and Credit Arrangements
Total net interest expense on Consolidated Statements of Operations	$ (3,979)	$ (3,636)	$ (11,275)	$ (11,230)
Interest paid, including payments made or received under the swaps	4,100	3,900	11,100	12,000
Interest expense | Interest rate swap
Debt and Credit Arrangements
Amount of Gain or (Loss) Recognized in AOCI/AOCL on Derivative	1,182	1,268	3,963	(7,219)
Amount of Gain or (Loss) Reclassified from AOCI/AOCL into Income	(1,644)	(1,674)	(5,084)	(3,376)
Total net interest expense on Consolidated Statements of Operations	$ 3,979	$ 3,636	$ 11,275	$ 11,230