Foreign Currency Hedging (Schedule of Foreign Currency Exchange Contracts Designated as Cash Flow Hedges) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Derivative [Line Items]
Notional Amount	$ 149,314	$ 210,667
Fair Value	(2,410)	(7,581)
Eurodollar Sell Forward Contract 1.230 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.230
Eurodollar Sell Forward Contract 1.240 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.240
Eurodollar Sell Forward Contract 1.270 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.270
Eurodollar Sell Forward Contract 1.281 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.281
Eurodollar Sell Forward Contract 1.300 [Member]
Derivative [Line Items]
Derivative, Forward Exchange Rate	1.300
Euro Forward Contracts [Member] | Eurodollar Sell Forward Contract 1.230 [Member]
Derivative [Line Items]
Notional Amount	0	27,553
Fair Value	0	(2,036)
Euro Forward Contracts [Member] | Eurodollar Sell Forward Contract 1.240 [Member]
Derivative [Line Items]
Notional Amount	10,850	10,850
Fair Value	(534)	(726)
Euro Forward Contracts [Member] | Eurodollar Sell Forward Contract 1.270 [Member]
Derivative [Line Items]
Notional Amount	44,450	44,450
Fair Value	(1,136)	(1,950)
Euro Forward Contracts [Member] | Eurodollar Sell Forward Contract 1.281 [Member]
Derivative [Line Items]
Notional Amount	36,814	36,814
Fair Value	(651)	(1,331)
Euro Forward Contracts [Member] | Eurodollar Sell Forward Contract 1.300 [Member]
Derivative [Line Items]
Notional Amount	57,200	91,000
Fair Value	$ (89)	$ (1,538)