Accounting Policies and Basis of Presentation - Narrative (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Oct. 31, 2013	Jan. 31, 2013	Oct. 31, 2013 Stock Option [Member]	Oct. 31, 2012 Stock Option [Member]	Oct. 31, 2013 Stock Option [Member]	Oct. 31, 2012 Stock Option [Member]	Oct. 31, 2013 Nonvested Shares [Member]	Oct. 31, 2012 Nonvested Shares [Member]	Oct. 31, 2013 Nonvested Shares [Member]	Oct. 31, 2012 Nonvested Shares [Member]	Oct. 31, 2013 Minimum [Member]	Oct. 31, 2013 Maximum [Member]
Significant Accounting Policies [Line Items]
Raw materials	$ 1.9	$ 1.8
Estimated useful lives of amortizable intangible assets											1 year	35 years
Unrecognized compensation expense	$ 4.6
Weighted average period for unrecognized compensation expense to be recognized	2 years 2 months 12 days
Method used to determine the fair value of share-based compensation granted	The Company determines the fair value of share-based compensation granted in the form of stock options using a lattice valuation model. In addition, the Company granted certain market based awards during the first, second and third quarter of fiscal 2014, which were valued using the Monte Carlo simulation model.
Antidilutive securities excluded from weighted average shares			1.3	1.1	1.3	1.1	0.3	0.3	0.3	0.3