CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 35,799	$ 27,684
Short-term investments	98,443	112,542
Accounts receivable, net of allowance for doubtful accounts of $902 and $890 in 2022 and 2021, respectively	37,753	40,087
Prepaid expenses and other current assets	8,857	8,194
Total current assets	180,852	188,507
Property and equipment, net	36,844	35,295
Operating lease right-of-use assets, net	4,479	5,408
Goodwill	14,123	14,123
Intangible assets, net	20,372	21,239
Deferred tax assets, net	67	75
Other non-current assets	8,840	9,121
Total assets	265,577	273,768
Current liabilities:
Accounts payable	4,053	5,554
Accrued compensation and related benefits	8,576	9,495
Accrued and other current liabilities	4,602	3,328
Operating lease liabilities - current portion	1,225	1,758
Deferred revenues - current portion	23,868	23,691
Billings in excess of recognized revenues	245
Total current liabilities	42,569	43,826
Long-term income taxes payable	2,666	2,656
Non-current operating lease liabilities	4,741	5,258
Other non-current liabilities	2,034	2,443
Total liabilities	52,010	54,183
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.00015 par value, 5,000 shares authorized, no shares issued and outstanding
Common stock, $0.00015 par value, 70,000 shares authorized; shares issued 47,929 and 47,414, respectively; shares outstanding 37,594 and 37,411, respectively	6	6
Additional paid-in-capital	430,799	423,069
Treasury stock at cost, 10,335 and 10,003 shares, respectively	(113,872)	(104,705)
Accumulated deficit	(101,871)	(97,721)
Accumulated other comprehensive loss	(1,495)	(1,064)
Total stockholders' equity	213,567	219,585
Total liabilities and stockholders' equity	$ 265,577	$ 273,768