Note 6 - Stock-Based Compensation (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020
Share-Based Payment Arrangement, Expense \| $	$ 1,445	$ 1,779
Share-based Compensation Arrangement by Share-based Payment Award, Number of Award Vesting Types	2
Director [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total \| $	$ 400	800
Performance Shares [Member]
Share-Based Payment Arrangement, Expense \| $	1,200	1,200
Share-Based Payment Arrangement, Expense, after Tax \| $	$ 0	$ 100
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)	22,000	67,000
Restricted Stock [Member] \| Director [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period (in shares)	165,000	83,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)	110,000	95,000
Restricted Stock [Member] \| Other Management [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Issued and Vested in Period (in shares)	82,000	60,000
Restricted Stock [Member] \| Non-Employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Issued and Vested in Period (in shares)	15,000	20,000
Performance Stock Unit [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period (in shares)	0	0
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)	0	1
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)	92,000	6,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Target Percentage			120.00%
Performance Based Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Nonvested Options Forfeited, Number of Shares (in shares)	11,000	11,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Nonvested, Number of Shares, Ending Balance (in shares)	0
Service Based Award [Member]
Share-Based Payment Arrangement, Expense, after Tax \| $	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	4 years
Share Based Compensation Arrangement, By Share Based Payment Award, Expiration Term (Year)	8 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures, Total (in shares)	0	0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures in Period (in shares)	0	5,000
2014 Equity Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	4,100,000
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	2,200,000
The 2020 Award [Member]
Share-Based Payment Arrangement, Expense \| $	$ 200	$ 500
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)	64,000	85,000

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The number of equity-based payment instruments, excluding stock (or unit) options, that issued and vested during the reporting period.

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the maximum target percentage for equity instruments other then options under share based payment arrangement.

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Represents the number of award vesting types under share-based compensation arrangement by share-based payment award.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number of shares authorized for issuance under share-based payment arrangement.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Number of non-vested options outstanding.

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