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Nominal or face amount used to calculate payments on the derivative asset.

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Fair value as of the balance sheet date of all foreign currency derivative assets not designated as hedging instruments.

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Derivative Financial Instruments - Notional Amount and Fair Value of Foreign Currency Forward Contract (Detail) In Thousands, unless otherwise specified	Sep. 30, 2013 Financial Institution Counterparties [Member] USD ($)	Dec. 31, 2012 Financial Institution Counterparties [Member] USD ($)	Sep. 30, 2013 Financial Institution Counterparties [Member] Other Assets [Member] Non Designated as Hedging Instrument [Member] CAD	Sep. 30, 2013 Financial Institution Counterparties [Member] Other Assets [Member] Non Designated as Hedging Instrument [Member] EUR (€)	Dec. 31, 2012 Financial Institution Counterparties [Member] Other Assets [Member] Non Designated as Hedging Instrument [Member] CAD	Dec. 31, 2012 Financial Institution Counterparties [Member] Other Assets [Member] Non Designated as Hedging Instrument [Member] EUR (€)	Sep. 30, 2013 Customer Counterparties [Member] USD ($)	Dec. 31, 2012 Customer Counterparties [Member] USD ($)	Sep. 30, 2013 Customer Counterparties [Member] Other Liabilities [Member] Non Designated as Hedging Instrument [Member] CAD	Dec. 31, 2012 Customer Counterparties [Member] Other Liabilities [Member] Non Designated as Hedging Instrument [Member] CAD
Derivative Counter Party [Line Items]
Forward contracts – assets (liabilities) Notional Amount			19,026	€ 1,117	0	€ 1,093
Forward contracts - assets (liabilities) Estimated Fair Value	(2)	3
Forward contracts – assets									19,001	0
Forward contracts – liabilities	(346)	0
Forward contracts – assets							$ 372	$ 0