Derivatives and Hedging Instruments - Summary of Fair Value of Derivative Instruments as Recorded in Company's Consolidated Statements of Financial Condition (Detail) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Foreign Currency Exchange Contracts [Member]
Derivatives designated as hedging instruments:
Foreign currency exchange contracts, assets	$ 6,828	$ 718
Foreign currency exchange contracts, liabilities	(3,623)	(601)
Interest Rate Swap [Member]
Derivatives not designated as hedging instruments:
Interest rate swap agreements, liabilities	(258)	(352)
Designated as Hedging Instrument [Member] | Foreign Currency Exchange Contracts [Member] | Other Assets [Member]
Derivatives designated as hedging instruments:
Foreign currency exchange contracts, assets	160	718
Designated as Hedging Instrument [Member] | Foreign Currency Exchange Contracts [Member] | Other Liabilities [Member]
Derivatives designated as hedging instruments:
Foreign currency exchange contracts, liabilities	(539)	(601)
Not Designated as Hedging Instrument [Member] | Foreign Currency Exchange Contracts [Member] | Other Assets [Member]
Derivatives designated as hedging instruments:
Foreign currency exchange contracts, assets	6,668	0
Not Designated as Hedging Instrument [Member] | Foreign Currency Exchange Contracts [Member] | Other Liabilities [Member]
Derivatives designated as hedging instruments:
Foreign currency exchange contracts, liabilities	(3,084)	0
Not Designated as Hedging Instrument [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives not designated as hedging instruments:
Interest rate swap agreements, liabilities	$ (258)	$ (352)