Fair Value Measurements and Disclosures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2020	Dec. 29, 2019
Measurement of financial assets and liabilities at fair value on a recurring basis
Transfers among levels within the fair value hierarchy	$ 0	$ 0
Measured on Recurring Basis | Level 1
Measurement of financial assets and liabilities at fair value on a recurring basis
Cash surrender value of life insurance policies	37,578	33,220
Measured on Recurring Basis | Level 2
Measurement of financial assets and liabilities at fair value on a recurring basis
Interest rate swap liabilities	13,452	6,168
Measured on Recurring Basis | Carrying Value
Measurement of financial assets and liabilities at fair value on a recurring basis
Cash surrender value of life insurance policies	37,578	33,220
Interest rate swap liabilities	$ 13,452	$ 6,168