Note 1 - Organization and Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2024

Notes Tables

Schedule of Cash and Cash Equivalents [Table Text Block]

	December 31, 2024		December 31, 2023
Cash	$	7,879	$	12,495
Cash equivalents		631		5,083
Total cash and cash equivalents shown in the Consolidated Statements of Cash Flows	$	8,510	$	17,578

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

	December 31,
	2024			2023
Held-to-maturity debt securities:
Amortized cost	$	21,059		$	15,800
Gross unrecognized gains		50			—
Gross unrecognized losses		(33	)		(86	)
Fair value	$	21,076		$	15,714

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amortized Cost		Fair Value
Within one year	$	10,184	$	10,200
After one year through two years		10,875		10,876
Total	$	21,059	$	21,076

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
2023	$	110	$	24	$	(23	)	$	111
2024	$	111	$	—	$	(5	)	$	106

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

	December 31,
	2024			2023
Foreign currency translation
Balance at beginning of period	$	(1,748	)	$	(1,728	)
Other comprehensive loss:
Foreign currency translation adjustments (1)		(167	)		(20	)
Balance at end of period	$	(1,915	)	$	(1,748	)
Total accumulated other comprehensive loss	$	(1,915	)	$	(1,748	)

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

			2024							2023
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		852		(525	)		327		826		(468	)		358
Total			$	852	$	(525	)	$	327	$	826	$	(468	)	$	358

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

Year	Estimated Amortization Expense
2025	$	36
2026		35
2027		35
2028		35
2029		29
Thereafter		157
Total	$	327

Property, Plant and Equipment [Table Text Block]

Description of Property and Equipment	Depreciable Life (years)		2024			2023
Land			$	1,050		$	1,050
Building		39		3,950			3,950
Building and leasehold improvements		3 - 39		2,677			2,655
Field equipment		3 - 4		13,004			12,100
Computer equipment and software		2 - 3		2,017			2,049
Furniture and fixtures		3 - 10		1,305			1,307
Vehicles		5		37			32
Construction in process				2			99
Total cost				24,042			23,242
Less accumulated depreciation				(18,958	)		(18,703	)
Total net book value			$	5,084		$	4,539

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

	2024		2023
Basic weighted-average shares		30,572,000		30,348,000
Conversion of unsecured loan notes		—		—
Unexercised options and unvested restricted stock units		—		—
Diluted weighted-average shares		30,572,000		30,348,000