Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 100,385	$ 97,605
Accounts receivable, net of allowance for doubtful accounts of $154 in 2020 and $213 in 2019	37,363	40,651
Prepaid expenses and other current assets	11,628	9,320
Total current assets	149,376	147,576
Property and equipment, net	41,009	40,798
Operating lease right-of-use assets, net	7,368	7,609
Goodwill	2,293	2,293
Intangible assets, net	5,904	6,221
Deferred tax assets	25,085	25,327
Other non-current assets	8,322	9,720
Total assets	239,357	239,544
Current liabilities:
Accounts payable	4,828	7,636
Accrued compensation and related benefits	4,754	5,072
Accrued and other current liabilities	1,406	1,665
Operating lease liabilities – current portion	1,954	1,867
Deferred revenues – current portion	12,326	10,639
Billings in excess of recognized revenues	1,796	1,117
Total current liabilities	27,064	27,996
Long-term income taxes payable	4,884	5,368
Non-current operating lease liabilities	7,310	7,677
Deferred revenues – non-current portion	(1,630)	(2,346)
Total liabilities	40,888	43,387
Commitments and contingencies (Note 12)
Stockholders’ equity:
Preferred stock, $0.00015 par value, 5,000 shares authorized, no shares issued and outstanding	0	0
Common stock, $0.00015 par value, 70,000 shares authorized; shares issued 42,182 and 41,797, respectively; shares outstanding 32,795 and 32,503, respectively	5	5
Additional paid-in-capital	329,681	325,197
Treasury stock at cost, 9,387 and 9,294 shares, respectively	(93,173)	(91,695)
Accumulated deficit	(36,398)	(35,870)
Accumulated other comprehensive loss	(1,646)	(1,480)
Total stockholders’ equity	198,469	196,157
Total liabilities and stockholders’ equity	$ 239,357	$ 239,544