Fair Value (Details) - USD ($) $ in Millions	Mar. 30, 2018	Dec. 31, 2017
Liabilities:
Equity securities held in rabbi trust	$ 17.4	$ 17.9
Other Liabilities
Liabilities:
Total aggregate costs to date	9.6	9.4
Recurring Basis
Assets:
Derivative assets	12.8	27.4
Equity securities	8.6	8.4
Total assets	21.4	35.8
Liabilities:
Derivative liabilities	2.1	0.8
Total liabilities	2.1	0.8
Recurring Basis | Level 1
Assets:
Derivative assets	0.0	0.0
Equity securities	8.6	8.4
Total assets	8.6	8.4
Liabilities:
Derivative liabilities	0.0	0.0
Total liabilities	0.0	0.0
Recurring Basis | Level 2
Assets:
Derivative assets	12.8	27.4
Equity securities	0.0	0.0
Total assets	12.8	27.4
Liabilities:
Derivative liabilities	2.1	0.8
Total liabilities	2.1	0.8
Recurring Basis | Level 3
Assets:
Derivative assets	0.0	0.0
Equity securities	0.0	0.0
Total assets	0.0	0.0
Liabilities:
Derivative liabilities	0.0	0.0
Total liabilities	$ 0.0	$ 0.0