Fair Value Measurements (Assets And Liabilities Measured At Fair Value On Recurring Basis) (Detail) - Recurring - USD ($) $ in Millions	Oct. 02, 2020	Jan. 03, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	$ 37.2	$ 36.2
Derivatives assets	0.4	0.3
Total assets measured at fair value	37.6	36.5
Deferred compensation plan liabilities	37.2	36.2
Derivatives liabilities	0.3	1.0
Contingent consideration liabilities	8.8	19.9
Total liabilities measured at fair value	46.3	57.1
Level I
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	37.2	36.2
Derivatives assets	0.0	0.0
Total assets measured at fair value	37.2	36.2
Deferred compensation plan liabilities	37.2	36.2
Derivatives liabilities	0.0	0.0
Contingent consideration liabilities	0.0	0.0
Total liabilities measured at fair value	37.2	36.2
Level II
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	0.0	0.0
Derivatives assets	0.4	0.3
Total assets measured at fair value	0.4	0.3
Deferred compensation plan liabilities	0.0	0.0
Derivatives liabilities	0.3	1.0
Contingent consideration liabilities	0.0	0.0
Total liabilities measured at fair value	0.3	1.0
Level III
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	0.0	0.0
Derivatives assets	0.0	0.0
Total assets measured at fair value	0.0	0.0
Deferred compensation plan liabilities	0.0	0.0
Derivatives liabilities	0.0	0.0
Contingent consideration liabilities	8.8	19.9
Total liabilities measured at fair value	$ 8.8	$ 19.9