CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 31,350	$ 44,583
Short-term investments	14,978	14,999
Accounts receivable, net	23,373	26,908
Prepaid expenses	8,095	6,641
Other current assets	878	922
Total current assets	78,674	94,053
Non-current assets:
Property and equipment, net	6,642	6,746
Operating lease right-of-use assets	14,993	15,821
Goodwill	99,175	99,175
Deferred income tax assets, net	32,684	31,653
Other non-current assets	707	706
Total non-current assets	154,201	154,101
Total assets	232,875	248,154
Current liabilities:
Accounts payable	3,863	5,292
Accrued compensation and benefits	15,769	13,948
Deferred revenue	24,223	25,608
Operating lease liabilities	5,112	5,405
Other current liabilities	5,147	4,745
Total current liabilities	54,114	54,998
Non-current liabilities:
Asset retirement obligations	6,372	6,355
Operating lease liabilities	11,256	11,883
Other non-current liabilities	1,238	1,227
Total non-current liabilities	18,866	19,465
Total liabilities	72,980	74,463
Commitments and contingencies (Note 13)
Stockholders' equity:
Preferred stock	0	0
Common stock	2	2
Additional paid-in capital	97,197	97,291
Accumulated other comprehensive loss	(1,563)	(1,588)
Retained earnings	64,259	77,986
Total stockholders’ equity	159,895	173,691
Total liabilities and stockholders' equity	$ 232,875	$ 248,154