Accumulated Other Comprehensive Loss - Reclassifications out of AOCI (Details) - USD ($) $ in Millions	3 Months Ended		4 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jul. 01, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income taxes	$ (1.0)	$ (80.7)			$ (82.7)	$ (160.4)
(Millions of Dollars)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax					(19.6)	2.1
(Millions of Dollars) | Other, net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax					(12.0)	9.7
(Millions of Dollars) | Other Expense [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax					7.5	0.0
(Millions of Dollars) | Interest Expense [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax					7.6	7.6
(Millions of Dollars) | Pension gains (losses), net of tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax					(7.8)	(20.8)
Income taxes					(2.0)	(5.9)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax					(5.8)	(14.9)
(Millions of Dollars) | Pension gains (losses), net of tax | Other Expense [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Actuarial losses, reclassification to Statements of Operations and Comprehensive Income			$ 0.0	$ 0.0	(7.8)	(8.0)
Cash Flow Hedges | (Millions of Dollars) | Unrealized gains (losses) on cash flow hedges, net of tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income taxes					7.9	(0.7)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax					11.7	1.4
Net Investment Hedging [Member] | (Millions of Dollars) | Unrealized gains (losses) on cash flow hedges, net of tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income taxes					(1.6)	0.0
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax					$ 5.9	$ 0.0