Derivatives And Financial Instruments (Schedule Of Classification Of Gains And Losses On Derivative Instruments) (Details) (USD $) In Thousands	3 Months Ended				6 Months Ended
	Jul. 31, 2011		Jul. 31, 2010		Jul. 31, 2011		Jul. 31, 2010
Recognized in Other Comprehensive Income (Loss)	$ 743		$ (1,379)		$ 5,374		$ (403)
Reclassified from Accumulated Other Comprehensive Income into Statement of Operations	3,324	[1]	(427)	[1]	5,553	[1]	(384)	[1]
Recognized in Other Income (Expense), Net	187		(1,556)		(1,685)		(2,806)
Foreign Currency Forward [Member] | Derivatives Designated As Hedging Instruments [Member]
Recognized in Other Comprehensive Income (Loss)	743		(1,379)		5,374		(403)
Reclassified from Accumulated Other Comprehensive Income into Statement of Operations	3,324	[1]	(427)	[1]	5,553	[1]	(384)	[1]
Interest Rate Swap [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Recognized in Other Income (Expense), Net			(1,501)				(3,102)
Foreign Currency Forward [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Recognized in Other Income (Expense), Net	$ 187		$ (55)		$ (1,685)		$ 296

[1] Amounts reclassified from accumulated other comprehensive income into the statement of operations are classified as operating expenses.