Information about Geographic Areas - Revenues by Geographic Area (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2012	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2012
Revenues by geography
Total revenues	$ 62,803	$ 54,979	$ 49,581	$ 42,788	$ 39,788	$ 35,796	$ 29,455	$ 24,509	$ 210,151	$ 129,548	$ 61,262
North America [Member]
Revenues by geography
Total revenues									124,451	84,546	48,088
Europe [Member]
Revenues by geography
Total revenues									49,944	29,036	10,433
Asia Pacific [Member]
Revenues by geography
Total revenues									$ 35,756	$ 15,966	$ 2,741