Summary of Notional Amounts for Foreign Currency Contracts (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Derivative
Notional amount for foreign currency derivatives designated as hedging instruments	$ 46,777	$ 33,219
Notional amount for foreign currency derivatives not designated as hedging instruments	61,138	71,353
Australian Dollar
Derivative
Notional amount for foreign currency derivatives designated as hedging instruments	3,678	4,078
Notional amount for foreign currency derivatives not designated as hedging instruments	6,779	8,138
Canadian Dollar
Derivative
Notional amount for foreign currency derivatives designated as hedging instruments	10,707	14,158
Chinese Yuan
Derivative
Notional amount for foreign currency derivatives designated as hedging instruments	3,398	2,777
Israeli Shekel
Derivative
Notional amount for foreign currency derivatives designated as hedging instruments	3,873	3,773
Russian Ruble
Derivative
Notional amount for foreign currency derivatives designated as hedging instruments	6,633	8,433
Euro
Derivative
Notional amount for foreign currency derivatives designated as hedging instruments	18,488
Notional amount for foreign currency derivatives not designated as hedging instruments	30,964	40,397
Danish Krone
Derivative
Notional amount for foreign currency derivatives not designated as hedging instruments	833	891
Norwegian Krone
Derivative
Notional amount for foreign currency derivatives not designated as hedging instruments	653	1,073
Swedish Krona
Derivative
Notional amount for foreign currency derivatives not designated as hedging instruments	1,236	446
South Korean Won
Derivative
Notional amount for foreign currency derivatives not designated as hedging instruments	2,106	2,193
Brazil Real
Derivative
Notional amount for foreign currency derivatives not designated as hedging instruments	2,924	3,826
Japanese Yen
Derivative
Notional amount for foreign currency derivatives not designated as hedging instruments	6,401	6,439
British Pound
Derivative
Notional amount for foreign currency derivatives not designated as hedging instruments	$ 9,242	$ 7,950