CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 21,823	$ 16,890
Short-term investments	28,931	36,519
Accounts receivable, net	10,224	9,567
Prepaid expenses and other current assets	980	1,211
Total current assets	61,958	64,187
Property and equipment, net	1,552	1,706
Intangible assets, net	256	266
Other assets	1,073	1,070
Total assets	64,839	67,229
Current liabilities:
Accounts payable	1,022	1,085
Accrued compensation	1,965	2,974
Other accrued liabilities	2,118	2,496
Short-term deferred revenue	2,876	2,759
Total current liabilities	7,981	9,314
Long-term deferred revenue	88	106
Other long-term liabilities	510	501
Total liabilities	8,579	9,921
Commitments and contingencies (Note 3)
Stockholders' equity:
Common stock; par value $0.0001, 50,000,000 shares authorized; 19,042,852 issued and 18,561,008 outstanding at March 31, 2017; 19,030,024 issued and 18,548,180 outstanding at December 31, 2016	2	2
Additional paid-in capital	267,490	267,400
Treasury stock, at cost (481,844 shares at March 31, 2017 and December 31, 2016)	(5,295)	(5,295)
Accumulated other comprehensive loss	(2,181)	(2,329)
Accumulated deficit	(203,756)	(202,470)
Total stockholders' equity	56,260	57,308
Total liabilities and stockholders' equity	$ 64,839	$ 67,229