Open Foreign Currency Contracts (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Derivative [Line Items]
Notional Amounts (in US Dollars)	$ 186,938
Net Unrealized Gain (Loss)	(1,855)
Cash Flow Hedging | Foreign currency contracts | Currency, Australian Dollar
Derivative [Line Items]
Notional Amounts (in US Dollars)	9,714
Net Unrealized Gain (Loss)	(14)
Cash Flow Hedging | Foreign currency contracts | Currency, Canadian Dollar
Derivative [Line Items]
Notional Amounts (in US Dollars)	136,211
Net Unrealized Gain (Loss)	(2,098)
Cash Flow Hedging | Foreign currency contracts | Currency, Swedish Krone
Derivative [Line Items]
Notional Amounts (in US Dollars)	11,301
Net Unrealized Gain (Loss)	(159)
Cash Flow Hedging | Foreign currency contracts | Currency, Japanese Yen
Derivative [Line Items]
Notional Amounts (in US Dollars)	10,986
Net Unrealized Gain (Loss)	77
Cash Flow Hedging | Foreign currency contracts | Currency, Mexican Peso
Derivative [Line Items]
Notional Amounts (in US Dollars)	10,483
Net Unrealized Gain (Loss)	818
Cash Flow Hedging | Foreign currency contracts | Currency, Euro
Derivative [Line Items]
Notional Amounts (in US Dollars)	8,243
Net Unrealized Gain (Loss)	$ (479)