Summary of Business and Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 31, 2013	Jul. 31, 2012	Jul. 31, 2013 Segment	Jul. 31, 2012	Jan. 31, 2013
Organization And Summary Of Significant Accounting Policies [Line Items]
Stock split of the common stock			On March 20, 2013, the Company's certificate of incorporation was amended to increase the number of authorized shares of common stock from 400.0 million to 1.6 billion in order to provide for a four-for-one stock split of the common stock effected in the form of a stock dividend.
Number of reportable operating segments			1
Percentage of customer accounts receivable required to be considered a significant customer			5.00%		5.00%
Customers exceeding concentration of accounts receivable threshold, number	0		0		0
Percentage of customer total revenue required to be considered a significant customer	5.00%	5.00%	5.00%	5.00%
Customers exceeding concentration of total revenue threshold, number	0	0	0	0
Stock-based expense recognized over vesting term, years			4 years
Before Stock Split
Organization And Summary Of Significant Accounting Policies [Line Items]
Common stock, shares authorized	400,000,000		400,000,000
After Stock Split
Organization And Summary Of Significant Accounting Policies [Line Items]
Common stock, shares authorized	1,600,000,000		1,600,000,000
Assets, Total | Outside Americas
Organization And Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage			9.00%		16.00%
Revenue | Outside Americas
Organization And Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	96.00%	94.00%	95.00%	94.00%
Minimum
Organization And Summary Of Significant Accounting Policies [Line Items]
Deferred and amortized commission period (in months)			12
Maximum
Organization And Summary Of Significant Accounting Policies [Line Items]
Deferred and amortized commission period (in months)			36