Changes in Accrued Special Charges (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Oct. 31, 2011
Restructuring and Related Cost [Abstract]
Accrued special charges beginning balance	$ 6,930
Charges	7,388
Payments	(9,714)
Accrued special charges ending balance	4,604	[1]
Employee severance and related costs
Restructuring and Related Cost [Abstract]
Accrued special charges beginning balance	2,664
Charges	3,581
Payments	(4,603)
Accrued special charges ending balance	1,642	[1]
Excess leased facility costs
Restructuring and Related Cost [Abstract]
Accrued special charges beginning balance	1,930
Charges	281
Payments	(597)
Accrued special charges ending balance	1,614	[1]
Other costs
Restructuring and Related Cost [Abstract]
Accrued special charges beginning balance	2,336
Charges	3,526
Payments	(4,514)
Accrued special charges ending balance	$ 1,348	[1]

[1] Of the $4,604 total accrued special charges as of October 31, 2011, $1,095 represented the long-term portion of accrued lease termination fees and other facility costs, net of sublease income. The remaining balance of $3,509 represented the short-term portion of accrued special charges.