CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income (loss)	$ 5,401	$ (20,044)
Adjustments to reconcile net income (loss) to net cash (used in) provided by operating activities:
Depreciation and amortization	1,931	2,197
Stock-based compensation	4,756	5,464
Impairment of right-of-use lease asset	271	939
Foreign currency remeasurement gains (losses)	(427)	102
Deferred income taxes	(2,483)	431
Other	127	(3)
Changes in operating assets and liabilities:
Accounts and other receivables	1,167	(2,334)
Prepaid expenses and other current assets	1,486	(4,374)
Long-term deposits	(5,077)	(6,870)
Other assets	2,194	(4,509)
Accounts payable	(660)	(2,815)
Accrued compensation	(1,843)	(1,104)
Other current liabilities	(1,253)	(728)
Deferred revenue	(4,137)	(4,150)
Other long-term liabilities	(1,431)	3,699
Net cash (used in) provided by operating activities	22	(34,099)
Cash flows provided by (used in) investing activities:
Purchases of short-term investments	0	(8,930)
Proceeds from maturities of short-term investments	3,000	20,000
Purchases of property and equipment	(47)	(150)
Net cash provided by investing activities	2,953	10,920
Cash flows provided by (used in) financing activities:
Proceeds from issuance of common stock under employee stock purchase plan	134	165
Proceeds from stock options exercise	577	1,245
Cash paid for purchases of treasury stock	(30,642)	(2,741)
Net cash used in financing activities	(29,931)	(1,331)
Net decrease in cash and cash equivalents	(26,956)	(24,510)
Cash and cash equivalents:
Beginning of year	86,478	110,988
End of year	59,522	86,478
Supplemental disclosure of cash flow information:
Cash paid for taxes	65	160
Disclosure of non-cash operating, investing, and financing activities:
Release of Restricted Stock Units and Awards under company stock plan	3,016	7,190
Leased assets obtained in exchange for new operating lease liabilities	$ 577	$ 0