Retirement and Other Employee Benefits (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Domestic Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1.6	$ 1.4	$ 4.8	$ 4.1
Interest cost	1.5	1.7	4.4	5.1
Expected return on assets	(0.6)	(0.8)	(1.8)	(2.4)
Amortization of net actuarial loss	0.3	0.1	0.9	0.4
Net periodic benefit costs	2.8	2.4	8.3	7.2
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit costs	$ 0.8	$ 0.7	$ 2.4	$ 2.2