Summary of Significant Accounting Policies - Estimated Useful Life of Assets (Detail)	12 Months Ended
	Jan. 31, 2014
Computer Equipment [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Computer Equipment [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Software [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Office Equipment and Furniture [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	3 years
Office Equipment and Furniture [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	5 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated Useful Life	Shorter of useful life or remaining life of lease