Note 2 - Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2023

Notes Tables

Schedule of Cash and Cash Equivalents [Table Text Block]

	March 31,		March 31,
	2023		2022
Cash	$	13,505	$	34,174
Cash equivalents		2,193		—
Restricted cash and cash equivalents included in current assets		—		1,066
Total cash, cash equivalents, and restricted cash and cash equivalents shown in the Condensed Consolidated Statements of Cash Flows	$	15,698	$	35,240

Debt Securities, Held-to-Maturity [Table Text Block]

	As of
Held-to-maturity debt securities:	March 31, 2023			December 31, 2022
Amortized cost	$	18,121		$	9,341
Gross unrecognized gains		—			—
Gross unrecognized losses		(148	)		(168	)
Fair value	$	17,973		$	9,173

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Within one year	$	11,067	$	11,012
After one year through two years		5,607		5,535
After two years through three years		1,447		1,426
Total	$	18,121	$	17,973

Financing Receivable, Allowance for Credit Loss [Table Text Block]

At January 1, 2022	$	223
Provision charged to expense		(19	)
(Write-offs) / Recoveries		(94	)
At December 31, 2022	$	110
Provision charged to expense		—
(Write-offs) / Recoveries		—
At March 31, 2023	$	110