CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jan. 31, 2013	Jan. 31, 2012
Preference shares, par value	$ 0.00045	$ 0.00000
Preference shares, shares authorized	20,000,000	0
Preference shares, shares issued	0	0
Preference shares, shares outstanding	0	0
Ordinary shares, par value	$ 0.00045	$ 0.00045
Ordinary shares, shares authorized	200,000,000	44,444,444
Ordinary shares, shares issued	27,035,074	7,600,869
Ordinary shares, shares outstanding	27,035,074	7,600,869
Series A Redeemable convertible preference shares [Member]
Redeemable convertible preference shares, par value		$ 0.00045
Redeemable convertible preference shares, shares authorized		5,611,111
Redeemable convertible preference shares, shares issued		5,611,107
Redeemable convertible preference shares, shares outstanding		5,611,107
Initial Liquidation Preference		$ 10,100
Series B Redeemable convertible preference shares [Member]
Redeemable convertible preference shares, par value		$ 0.00045
Redeemable convertible preference shares, shares authorized		3,665,550
Redeemable convertible preference shares, shares issued		3,629,253
Redeemable convertible preference shares, shares outstanding		3,629,253
Initial Liquidation Preference		13,000
Series C Redeemable convertible preference shares [Member]
Redeemable convertible preference shares, par value		$ 0.00045
Redeemable convertible preference shares, shares authorized		3,027,777
Redeemable convertible preference shares, shares issued		3,027,771
Redeemable convertible preference shares, shares outstanding		3,027,771
Initial Liquidation Preference		16,350
Series D Redeemable convertible preference shares [Member]
Redeemable convertible preference shares, par value		$ 0.00045
Redeemable convertible preference shares, shares authorized		2,222,222
Redeemable convertible preference shares, shares issued		1,047,596
Redeemable convertible preference shares, shares outstanding		1,047,596
Initial Liquidation Preference		$ 11,785