Other Non-Operating Income and Expenses, Net (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Other Non-Operating Income and Expenses, Net [Abstract]
Post-retirement income		$ (3)	$ (4)	$ (10)	$ (11)
Interest income		(1)	0	(3)	(38)
Miscellaneous expense		1	0	3	7
Other expense (income), net		92	(4)	85	(42)
Reclassification of unrealized loss into earnings from dedesignated interest rate swaps (2)	[1]	$ 95	$ 0	$ 95	$ 0

[1] Amounts for dedesignated cash flow hedges reclassified from accumulated other comprehensive income (loss) to net income (loss) were included in other expense (income), net in the Company's Consolidated Condensed Statements of Operations.