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Stockholders' Equity and Stock-Based Compensation Stock Option Awards (Details) - USD ($) $ in Millions				12 Months Ended
	Jan. 25, 2019	Jan. 29, 2018	Feb. 06, 2017	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, Weighted-average remaining contractual life (in years)				6 years 6 months	6 years 10 months 24 days	7 years 3 months 18 days	8 years 4 months 24 days
Granted (in shares)				610,953	637,115	956,809
Proceeds from stock options exercised				$ 0.1	$ 0.2	$ 0.1
Share-based Payment Arrangement, Exercise of Option, Tax Benefit				0.7	0.1	0.1
Exercises in period, intrinsic value				4.7	1.1	0.2
Vested in period, fair value				15.5	$ 12.5	$ 11.3
Outstanding, intrinsic value				53.4
Exercisable, intrinsic value				41.1
Total compensation cost not yet recognized				$ 6.9
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 7 months 6 days
Nonqualified Stock Options Under Long Term Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	610,953	637,115	956,809
Award vesting rights, percentage				33.33%
Expiration period				10 years