Restructuring Reserve (Detail)	3 Months Ended
Apr. 30, 2011 RestructuringFiscal2011Plan	Jul. 31, 2009 RestructuringFiscal2010Plan	Jan. 31, 2009 RestructuringFiscal2009Plan
Restructuring Cost and Reserve
Restructuring program, reduced the number of employees	200	430	700
Leased facilities that were consolidated	0	32	27

The number of positions eliminated during the period as a result of restructuring activities.

No definition available.

Name:	us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration