Note 1 - Organization and Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Notes Tables

Schedule of Cash and Cash Equivalents [Table Text Block]

	December 31, 2021		December 31, 2020
Cash and cash equivalents	$	35,893	$	10,640
Restricted cash included in current assets		891		1,595
Restricted cash included in long-term assets		270		371
Total cash, cash equivalents, and restricted cash shown in the Consolidated Statements of Cash Flows	$	37,054	$	12,606

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

Year	Balance at January 1		Provision charged to expense			Write-offs / Recoveries			Balance at December 31
2020	$	1,816	$	(498	)	$	(483	)	$	835
2021	$	835	$	227		$	(839	)	$	223

Schedule of Excess and Obsolete Inventory Reserve [Table Text Block]

Year	Balance at January 1		Provision charged to expense		Write-offs / Recoveries			Balance at December 31
2020	$	1,000	$	—	$	(93	)	$	907
2021	$	907	$	—	$	20		$	927

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

	December 31,
	2021			2020
Foreign currency translation
Balance at beginning of period	$	(1,370	)	$	(1,778	)
Other comprehensive income (loss):
Foreign currency translation adjustments (1)		(234	)		408
Balance at end of period	$	(1,604	)	$	(1,370	)
Total accumulated other comprehensive loss	$	(1,604	)	$	(1,370	)

Schedule of Finite-Lived Intangible Assets [Table Text Block]

			2021							2020
Description of Other Intangibles	Amortization Period (years)		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Patent assets		1 - 20		789		(341	)		448		1,310		(757	)		553
Total			$	789	$	(341	)	$	448	$	1,310	$	(757	)	$	553

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

Year	Estimated Amortization Expense
2022	$	57
2023		57
2024		49
2025		28
2026		28
Thereafter		229
Total	$	448

Property, Plant and Equipment [Table Text Block]

Description of Property and Equipment	Depreciable Life (years)		2021			2020
Land			$	1,050		$	1,050
Building		39		3,950			3,950
Building and leasehold improvements		3 - 39		2,626			2,886
Field equipment		3 - 4		11,787			19,748
Computer equipment and software		2 - 3		2,099			2,954
Furniture and fixtures		3 - 10		1,308			1,477
Vehicles		5		32			32
Construction in process				—			12
Total cost				22,852			32,109
Less accumulated depreciation				(18,243	)		(26,889	)
Total net book value			$	4,609		$	5,220

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	2021		2020
Basic weighted-average shares		29,585,000		24,691,000
Conversion of unsecured loan notes		—		—
Unexercised options and unvested restricted stock units		109,000		—
Diluted weighted-average shares		29,694,000		24,691,000