Derivative Financial Instruments - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash Flow Hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maximum length of future cash flow hedges	4 years 7 months 6 days
Recognized gain on the ineffective portion	$ 0	$ 0	$ 0
Accumulated net loss on derivative contracts included in accumulated other comprehensive income expected to be recognized in the Consolidated Statements of Comprehensive Income in the following 12 months, net of tax	800,000
Gains or losses reclassified out of AOCI into net income based on the probability that the original forecasted transaction would not occur	(300,000)	$ 0	$ 0
Interest-Rate Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount of outstanding contracts	2,977,800,000
Notional maturities for interest-rate contracts 2017	706,800,000
Notional maturities for interest-rate contracts 2018	1,041,900,000
Notional maturities for interest-rate contracts 2019	863,600,000
Notional maturities for interest-rate contracts 2020	174,100,000
Notional maturities for interest-rate contracts 2021	191,400,000
Notional maturities for interest-rate contracts thereafter	0
Foreign-exchange contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative notional amount outstanding	$ 522,400,000
Foreign-exchange contracts maturity period	Within one year