Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jan. 31, 2015	Jan. 31, 2014
Current assets:
Cash and cash equivalents	$ 170,291	$ 143,394
Marketable securities	37,703
Accounts receivable, net	40,180	18,837
Inventories	21,693	10,452
Restricted cash	8	3
Deferred tax assets, current	1,990	1,599
Prepaid expenses and other current assets	3,506	2,951
Total current assets	275,371	177,236
Property and equipment, net	3,075	3,018
Deferred tax assets, non-current	3,936	1,134
Other assets	1,902	1,919
Total assets	284,284	183,307
Current liabilities:
Accounts payable	21,036	8,321
Accrued liabilities	18,699	11,705
Income taxes payable	748	545
Deferred tax liabilities, current	92
Deferred revenue, current	4,907	4,831
Total current liabilities	45,482	25,402
Deferred revenue, non-current	198
Other long-term liabilities	1,393	1,544
Total liabilities	47,073	26,946
Commitments and contingencies (Note 11)
Shareholders' equity:
Preference shares, $0.00045 par value per share, 20,000,000 shares authorized and no shares issued and outstanding at January 31, 2015 and January 31, 2014, respectively
Ordinary shares, $0.00045 par value per share, 200,000,000 shares authorized at January 31, 2015 and January 31, 2014, respectively; 30,837,529 shares issued and outstanding at January 31, 2015; 28,748,513 shares issued and outstanding at January 31, 2014	14	13
Additional paid-in capital	140,564	110,285
Accumulated other comprehensive income (loss)	(1)
Retained earnings	96,634	46,063
Total shareholders’ equity	237,211	156,361
Total liabilities and shareholders' equity	$ 284,284	$ 183,307