Note 1 - Organization and Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2025

Notes Tables

Schedule of Cash and Cash Equivalents [Table Text Block]

	December 31, 2025		December 31, 2024
Cash	$	9,318	$	7,879
Cash equivalents		2,621		631
Total cash and cash equivalents shown in the Consolidated Statements of Cash Flows	$	11,939	$	8,510

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

	December 31,
	2025		2024
Held-to-maturity debt securities:
Amortized cost	$	19,933	$	21,059
Gross unrecognized gains		76		50
Gross unrecognized losses		—		(33	)
Fair value	$	20,009	$	21,076

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Within one year	$	12,942	$	12,981
After one year through two years		6,005		6,028
After two years through three years		986		1,000
Total	$	19,933	$	20,009

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
2024	$	111	$	—	$	(5	)	$	106
2025	$	106	$	—	$	2		$	108

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

	December 31,
	2025			2024
Foreign currency translation
Balance at beginning of period	$	(1,915	)	$	(1,748	)
Other comprehensive loss:
Foreign currency translation adjustments (1)		197			(167	)
Balance at end of period	$	(1,718	)	$	(1,915	)
Total accumulated other comprehensive loss	$	(1,718	)	$	(1,915	)

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

			2025							2024
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		867		(561	)		306		852		(525	)		327
Other intangible assets		10		340		—			340		—		—			—
Total			$	1,207	$	(561	)	$	646	$	852	$	(525	)	$	327

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

Year	Estimated Amortization Expense
2026	$	70
2027		70
2028		70
2029		65
2030		60
Thereafter		311
Total	$	646

Property, Plant and Equipment [Table Text Block]

Description of Property and Equipment	Depreciable Life (years)		2025			2024
Land			$	1,050		$	1,050
Building		39		3,950			3,950
Building and leasehold improvements		3 - 39		2,704			2,677
Field equipment		3 - 4		13,037			13,004
Computer equipment and software		2 - 3		2,057			2,017
Furniture and fixtures		3 - 10		1,318			1,305
Vehicles		5		37			37
Construction in process				19			2
Total cost				24,172			24,042
Less accumulated depreciation				(19,433	)		(18,958	)
Total net book value			$	4,739		$	5,084

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

	2025		2024
Basic weighted-average shares		30,937,000		30,572,000
Conversion of unsecured loan notes		—		—
Unexercised options and unvested restricted stock units		—		—
Diluted weighted-average shares		30,937,000		30,572,000