Retirement Plans (Defined Contribution Plan) (Details) $ in Millions	12 Months Ended
	Dec. 27, 2019 USD ($) contract	Dec. 28, 2018 USD ($) contract	Dec. 29, 2017 USD ($)
Defined Contribution Plan Disclosure [Line Items]
Number of Life Insurance Contract Held in Rabbi Trust | contract	62	118
Defined Contribution Plan, 401 K [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent of match	50.00%
Defined Contribution Plan, Cost | $	$ 21.9	$ 25.3	$ 25.2