Note 6 - Stock-Based Compensation (Details Textual) shares in Thousands, $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($) shares
Share-based Payment Arrangement, Expense \| $	$ 1,779	$ 965
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 \| $	$ 800	500
Performance Shares [Member]
Share-based Payment Arrangement, Expense \| $	1,200	1,000
Share-based Payment Arrangement, Expense, after Tax \| $	$ 100	$ 700
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)	67	96
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)		10
Restricted Stock [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period (in shares)	83	93
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)	95	78
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)	60	0
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)	20
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)	1	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period (in shares)	6	129
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	72
Service Based Award [Member]
Share-based Payment Arrangement, Expense \| $	$ 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, Forfeitures in Period (in shares)	5	62
Deferred Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period (in shares)	0	0
2014 Equity Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)	4,100
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	2,600
The 2020 Award [Member]
Share-based Payment Arrangement, Expense \| $	$ 500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (in shares)	85

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

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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 shares issued under share-based payment arrangement.

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Number of non-vested options forfeited.

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