Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 56,083	$ 91,282
Short-term investments	142,706	60,878
Accounts receivable, net of allowance for doubtful accounts of $800 and $400 as of December 31, 2014 and 2013, respectively	59,553	44,638
Inventories	21,064	16,748
Deferred costs	4,414	4,207
Deferred tax assets	6,205	7,715
Prepaid expenses and other current assets	5,367	5,227
Total current assets	295,392	230,695
Property and equipment, net	13,636	11,472
Goodwill	9,945	9,945
Intangible assets, net	7,351	9,671
Non-current deferred tax asset	21,166	15,317
Restricted cash	5,000	5,000
Other assets	1,504	1,122
Total assets	353,994	283,222
Current liabilities:
Accounts payable	23,538	19,131
Accrued compensation	13,765	11,759
Accrued liabilities	5,282	6,231
Deferred revenue	39,231	33,139
Total current liabilities	81,816	70,260
Non-current deferred revenue	10,554	7,098
Non-current deferred tax liabilities	596	854
Other non-current liabilities	1,379	1,161
Total liabilities	94,345	79,373
Commitments and contingencies (Note 8)
Stockholders’ equity:
Common stock, $0.001 par value; 250,000 shares authorized as of December 31, 2014 and 2013; 85,110 and 80,691 shares issued and outstanding at December 31, 2014 and 2013, respectively	85	81
Additional paid-in capital	273,276	225,575
Accumulated other comprehensive loss	(97)	(2)
Accumulated deficit	(13,615)	(21,805)
Total stockholders’ equity	259,649	203,849
Total liabilities and stockholders’ equity	$ 353,994	$ 283,222