Retirement Benefits (Details 6) - USD ($) $ in Millions	Dec. 31, 2023	Jan. 01, 2023
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Current assets	$ 2.4	$ 0.0
Noncurrent assets	33.6	12.5
Current liabilities	(5.6)	(5.7)
Noncurrent liabilities	(39.7)	(225.6)
Total amount recognized	(9.3)	(218.8)
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Current assets	0.0	0.0
Noncurrent assets	0.0	0.0
Current liabilities	(26.4)	(27.8)
Noncurrent liabilities	(175.2)	(184.9)
Total amount recognized	$ (201.6)	$ (212.7)