Pension Benefits - Schedule of Assumptions Used (Details) - Pension Plan	12 Months Ended
	Dec. 27, 2020	Dec. 29, 2019	Dec. 30, 2018
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Calculation term, market-related value (in years)	3 years
Qualified Plan
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	2.64%	3.30%
Rate of increase in compensation levels	3.00%	3.00%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate for determining projected benefit obligation	3.30%	4.43%	3.75%
Discount rate in effect for determining service cost	3.67%	3.87%	3.88%
Discount rate in effect for determining interest cost	2.70%	4.06%	3.31%
Rate of increase in compensation levels	3.00%	3.00%	2.95%
Expected long-term rate of return on assets	4.59%	5.68%	5.69%
Nonqualified Plan
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	2.39%	3.17%
Rate of increase in compensation levels	2.50%	2.50%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate for determining projected benefit obligation	3.17%	4.35%	3.67%
Discount rate in effect for determining interest cost	2.78%	3.94%	3.14%
Rate of increase in compensation levels	2.50%	2.50%	2.50%