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Stockholders' Equity and Stock-Based Compensation Stock Option Awards (Details) - USD ($) $ in Millions				12 Months Ended
	Jan. 06, 2020	Jan. 25, 2019	Jan. 29, 2018	Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, Weighted-average remaining contractual life (in years)				6 years 2 months 12 days	6 years 6 months	6 years 10 months 24 days	7 years 3 months 18 days
Granted (in shares)				550,941	610,953	637,115
Proceeds from stock options exercised				$ 0.1	$ 0.1	$ 0.2
Share-based Payment Arrangement, Exercise of Option, Tax Benefit				2.4	0.4	0.2
Exercises in period, intrinsic value				19.5	4.7	1.1
Vested in period, fair value				17.4	$ 15.5	$ 12.5
Outstanding, intrinsic value				149.0
Exercisable, intrinsic value				110.2
Total compensation cost not yet recognized				$ 7.4
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				1 year 2 months 12 days
Options exercisable, Weighted-average remaining contractual life (in years)				5 years 3 months 18 days
Nonqualified Stock Options Under Long Term Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	550,941	610,953	637,115
Award vesting rights, percentage				33.33%
Expiration period				10 years
Incentive Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Issued, Shares, Share-based Payment Arrangement, before Forfeiture				0	0	0