Fair Value Measurements (Assets And Liabilities Measured At Fair Value On Recurring Basis) (Detail) - Recurring - USD ($) $ in Millions	Jul. 02, 2021	Jan. 01, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	$ 45.1	$ 41.9
Derivatives assets	0.3	0.9
Total assets measured at fair value	45.4	42.8
Deferred compensation plan liabilities	45.1	41.9
Derivatives liabilities	0.2	0.5
Contingent consideration liabilities	14.1	12.3
Total liabilities measured at fair value	59.4	54.7
(Level I)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan assets	45.1	41.9
Derivatives assets	0.0	0.0
Total assets measured at fair value	45.1	41.9
Deferred compensation plan liabilities	45.1	41.9
Derivatives liabilities	0.0	0.0
Contingent consideration liabilities	0.0	0.0
Total liabilities measured at fair value	45.1	41.9
(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	0.3	0.9
Total assets measured at fair value	0.3	0.9
Deferred compensation plan liabilities	0.0	0.0
Derivatives liabilities	0.2	0.5
Contingent consideration liabilities	0.0	0.0
Total liabilities measured at fair value	0.2	0.5
(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	14.1	12.3
Total liabilities measured at fair value	$ 14.1	$ 12.3