Effect of New Accounting Pronouncements - Additional Information (Detail) - USD ($)		12 Months Ended
	Jan. 01, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax benefit recognized		$ (121,100,000)	$ (88,100,000)	$ (95,600,000)
Reclassification of payments from investing activities to operating activities		854,200,000	649,600,000	686,100,000
Reclassification of payments from investing activities to financing activities		(47,800,000)	(11,600,000)	(31,700,000)
Cash paid for acquisitions, net of cash and restricted cash		376,100,000	243,400,000	249,600,000
Effect of changes in foreign exchange rates on cash, cash equivalents and restricted cash		$ 72,000,000	(107,600,000)	(75,000,000)
Description of contracts renewal period		One year or less
Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect on retained earnings	$ 100,000,000
Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect on retained earnings	$ 180,000,000
Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of payments from investing activities to operating activities			22,800,000	12,100,000
Reclassification of payments from investing activities to financing activities			45,500,000	21,800,000
Accounting Standards Update 2016-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax benefit recognized		$ 15,100,000	6,500,000	5,300,000
Accounting Standards Update 2016-18 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by operating activities			50,300,000	45,600,000
Cash paid for acquisitions, net of cash and restricted cash			15,600,000	58,800,000
Effect of changes in foreign exchange rates on cash, cash equivalents and restricted cash			$ 85,900,000	$ 59,900,000