Accumulated Other Comprehensive Income - Changes in Components of Accumulated Other Comprehensive Income, Net of Tax (Detail) $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($)
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	$ 11,271.3
AOCI before reclassifications	25.6
Reclassifications to statement of earnings	(10.0)
Stockholders Equity, Ending Balance	11,659.1
Cash Flow Hedges [Member]
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	20.9
AOCI before reclassifications	14.9
Reclassifications to statement of earnings	(14.4)
Stockholders Equity, Ending Balance	21.4
Foreign Currency Translation [Member]
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	(31.3)
AOCI before reclassifications	10.7
Stockholders Equity, Ending Balance	(20.6)
Defined Benefit Plan Items [Member]
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	(177.0)
Reclassifications to statement of earnings	4.4
Stockholders Equity, Ending Balance	(172.6)
Total AOCI [Member]
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	(187.4)
Stockholders Equity, Ending Balance	$ (171.8)