Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2010
Income Taxes [Line Items]
U.S. federal income tax rate	34.00%	34.00%	34.00%
Deferred tax liabilities, not recognized	2.9
Cumulative undistributed earnings of foreign subsidiaries	$ 18,400,000
Gross deferred tax assets, net of deferred tax liabilities before valuation allowance	3,598,000	2,768,000
Unrecognized tax benefits	3,018,000	2,213,000	2,007,000	1,883,000
Unrecognized tax benefits that would impact effective tax rate	2,100,000
Income tax liabilities considered as other long term liabilities	1,200,000	1,100,000
Interest expense and penalties related to uncertain tax positions	23,000	37,000	22,000
Interest and penalties related to uncertain tax positions	116,000	93,000
Income taxes payable, including estimated interest and penalties	1,400,000
California state [Member]
Income Taxes [Line Items]
Research and development credit carryforwards	1,800,000
State tax [Member]
Income Taxes [Line Items]
Credit carry forwards for valuation allowance	$ 100,000