Pension Plans - Net Periodic Pension Cost (Detail) - Pension Plans, Defined Benefit - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 6.7	$ 5.9	$ 20.2	$ 17.7
Interest cost	12.2	14.1	36.6	42.3
Expected return on plan assets	(23.7)	(22.8)	(71.1)	(68.3)
Amortization of unrecognized loss	8.7	6.3	25.9	18.8
Amortization of prior service credit	0.0	(0.2)	0.0	(0.6)
Net periodic cost	$ 3.9	$ 3.3	$ 11.6	$ 9.9