Retirement Benefits - Schedule of Defined Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2025	Dec. 29, 2024	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Recognized actuarial loss (gain) - mark to market	$ 18.6	$ 14.1	$ 26.8
Settlement loss	0.0	0.0	41.7
Total retirement benefit expense (income)	34.6	29.0	79.7
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the year	5.3	5.8	6.0
Interest cost on benefits earned in prior years	17.4	16.4	79.7
Expected return on plan assets	(15.9)	(16.4)	(84.8)
Amortization of prior service cost (credit)	0.4	0.3	0.3
Amortization of net actuarial loss	0.0	0.0	0.0
Recognized actuarial loss (gain) - mark to market	18.6	14.1	26.8
Settlement loss	0.0	0.0	41.7
Total retirement benefit expense (income)	25.8	20.2	69.7
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost - benefits earned during the year	0.4	0.5	0.6
Interest cost on benefits earned in prior years	9.9	10.2	10.9
Expected return on plan assets	0.0	0.0	0.0
Amortization of prior service cost (credit)	(0.9)	(0.8)	(0.9)
Amortization of net actuarial loss	5.1	5.2	6.0
Recognized actuarial loss (gain) - mark to market	0.0	0.0	0.0
Settlement loss	0.0	0.0	0.0
Total retirement benefit expense (income)	$ 14.5	$ 15.1	$ 16.6