Fair Value Measurements - Financial Assets and Liabilities Measured on a Recurring Basis at Fair Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Mutual fund assets	$ 24,055	$ 20,910
Derivative assets:
Foreign currency contracts	453	112
Total assets at fair value	24,508	21,022
Derivative liabilities:
Foreign currency contracts	469	305
Interest rate contracts		53
Total liabilities at fair value		358
Level 1 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Mutual fund assets	24,055	20,910
Derivative assets:
Total assets at fair value	24,055	20,910
Level 2 [Member]
Derivative assets:
Foreign currency contracts	453	112
Total assets at fair value	453	112
Derivative liabilities:
Foreign currency contracts	$ 469	305
Interest rate contracts		53
Total liabilities at fair value		$ 358