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Share-Based Awards, Purchase Plans and Compensation Cost (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 25, 2020	Dec. 27, 2019
Share-based Compensation Arrangement by Share-based Payment Award
Award expiration period	10 years
Stock Appreciation Plan Expense	$ 3.1	$ 2.4	$ 3.3
Intrinsic value of exercisable option shares	$ 342.0
Exercisable option weighted average contractual term	4 years 10 months 24 days
Share options vested and expected to vest	9,600,000
Aggregate intrinsic value of share options vested and expected to vest	$ 395.6
Weighted average exercise price of share options vested and expected to vest (per share)	$ 39.31
Weighted average contractual term of share options vested and expected to vest	5 years 8 months 12 days
Employee stock purchase plan shares granted	415,995	399,567	397,833
Unrecognized compensation cost related to unvested options	$ 9.8
Weighted average recognition period for unvested options	2 years 4 months 24 days
Stock Incentive Plan (2019) \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award
Shares issued under the plan	12,070	15,243	15,016
Employee Stock Purchase Plan (2006)
Share-based Compensation Arrangement by Share-based Payment Award
Share purchase price as percentage of fair value	85.00%
Stock purchase plan discount percentage	15.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting period	3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting period	4 years