Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2011
Allowance for doubtful accounts	$ 305	$ 305	$ 300
Preferred stock, par value	$ 0.00001	$ 0.00001
Preferred stock, shares authorized	10,000,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.00001	$ 0.00001
Common stock, shares authorized	0	140,000,000
Common stock, shares issued	0	24,843,851
Common stock, shares outstanding	0	24,843,851
Series A convertible preferred stock [Member]
Preferred stock, par value	$ 0.00001	$ 0.00001
Preferred stock, shares authorized	0	60,000,000
Preferred stock, shares issued	0	60,000,000
Preferred stock, shares outstanding	0	60,000,000
Series B convertible preferred stock [Member]
Preferred stock, par value	$ 0.00001	$ 0.00001
Preferred stock, shares authorized	0	26,562,500
Preferred stock, shares issued	0	25,000,000
Preferred stock, shares outstanding	0	25,000,000
Class A common stock [Member]
Common stock, par value	$ 0.00001	$ 0.00001
Common stock, shares authorized	800,000,000	0
Common stock, shares issued	15,044,750	0
Common stock, shares outstanding	15,044,750	0
Class B common stock [Member]
Common stock, par value	$ 0.00001	$ 0.00001
Common stock, shares authorized	190,000,000	0
Common stock, shares issued	109,746,795	0
Common stock, shares outstanding	109,746,795	0