Accumulated Other Comprehensive Income - Changes in Components of Accumulated Other Comprehensive Income, Net of Tax (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	$ 11,735.8
AOCI before reclassifications	62.3
Reclassifications to retained earnings	(42.9)
Reclassifications to statement of earnings	12.5
Stockholders Equity, Ending Balance	11,998.4
Foreign Currency Translation [Member]
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	121.5
AOCI before reclassifications	94.8
Reclassifications to retained earnings	(17.4)
Stockholders Equity, Ending Balance	198.9
Defined Benefit Plan Items [Member]
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	(138.2)
AOCI before reclassifications	(6.1)
Reclassifications to retained earnings	(21.1)
Reclassifications to statement of earnings	2.8
Stockholders Equity, Ending Balance	(162.6)
Total AOCI [Member]
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	(83.2)
Stockholders Equity, Ending Balance	(51.3)
Cash Flow Hedges [Member]
Other Comprehensive Income Loss [Line Items]
Stockholders Equity, Beginning Balance	(66.5)
AOCI before reclassifications	(26.4)
Reclassifications to retained earnings	(4.4)
Reclassifications to statement of earnings	9.7
Stockholders Equity, Ending Balance	$ (87.6)