Derivative Instruments And Hedging Activities (Narrative) (Detail) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Derivative Instruments And Hedging Activities [Line Items]
Notional value of foreign exchange contracts	$ 295,000,000	$ 178,000,000
Net cash outflow/inflow from settlement of derivative contracts	4,900,000	13,000,000
Derivatives Assets	1,703,000	2,617,000
Derivatives Liabilities	$ 3,173,000	$ 172,000