Prepaid expenses (Details - Prepaid Expenses) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Prepaid Expenses
Prepaid insurance	$ 105	$ 47
Prepaid rent	14	33
Prepaid licenses	80	3
Prepaid maintenance	0	1
Prepaid other	157	286
Prepaid expenses	$ 356	$ 370

Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_PrepaidInsurance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant