Derivative Instruments And Hedging Activities - Additional Information (Detail) - Derivatives Designated as Accounting Hedges [Member] - 2015 Senior Notes [Member] € in Millions, $ in Millions	Mar. 31, 2018 EUR (€)	Mar. 31, 2018 USD ($)
Currency Swap [Member] | Cross-Currency Paid [Member]
Derivative [Line Items]
Notional amount | $		$ 110.5
Derivative, swaption interest rate	3.945%	3.945%
Currency Swap [Member] | Cross-Currency Received [Member]
Derivative [Line Items]
Notional amount	€ 100.0
Derivative, swaption interest rate	1.75%	1.75%
Net Investment Hedging [Member] | Cross-Currency Paid [Member]
Derivative [Line Items]
Notional amount	€ 500.0