Note 4 - Balance Sheet Details - Summary of Other Noncurrent Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Disclosure Text Block [Abstract]
Prepaid Expense, Noncurrent	$ 734	$ 868
Other noncurrent assets	12
Other noncurrent assets, total	$ 746	$ 868

Sum of the carrying amounts as of the balance sheet date of amounts paid in advance for expenses which will be charged against earnings in periods after one year or beyond the operating cycle, if longer.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_PrepaidExpenseNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant