Significant Accounting Policies - Summary of Liabilities Related to Integration Plans (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($)
Schedule Of Business Acquisitions Liabilities Related To Integration Plans [Line Items]
Beginning Balance	$ 102.8
Additions	90.7
Cash payments	(119.0)
Foreign currency exchange rate changes	(1.3)
Closing Balance	73.2
Employee Termination Benefits [Member]
Schedule Of Business Acquisitions Liabilities Related To Integration Plans [Line Items]
Beginning Balance	46.8
Additions	50.8
Cash payments	(58.4)
Foreign currency exchange rate changes	(1.1)
Closing Balance	38.1
Contract Terminations [Member]
Schedule Of Business Acquisitions Liabilities Related To Integration Plans [Line Items]
Beginning Balance	56.0
Additions	39.9
Cash payments	(60.6)
Foreign currency exchange rate changes	(0.2)
Closing Balance	$ 35.1