The minimum aggregate value of ownership required for the board of directors.

No definition available.

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- Definition

The amount of monthly meeting fees that a director could receive in cash.

+ References

No definition available.

+ Details

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- Definition

The amount of vested restricted stock the a director can receive for monthly meeting fees.

+ References

No definition available.

+ Details

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- Definition

The amount of vested restricted stock issued for regular quarterly retainer.

+ References

No definition available.

+ Details

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- Definition

The number of options acquired during the period under share based payment arrangement.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	debit
Period Type:	duration

- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
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-Paragraph 2
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Period Type:	duration

- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

+ Details

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

+ Details

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- Definition

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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-Publisher FASB
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Period Type:	duration

- Definition

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

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
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- Definition

Number of shares issued under share-based payment arrangement.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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-Publisher FASB
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Note 10 - Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended		135 Months Ended
	Apr. 01, 2019	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Dec. 31, 2020	Feb. 20, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)		0		0
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 0		$ 0
Regular Quarterly Retainer of Vested Restricted Stock		10,000
Monthly Meeting Fees Director Could Receive in Cash		800
Monthly Meeting Fees Director Could Receive in Vested Restricted Stock		1,000
Minimum Aggregate Value of Ownership Required for Board of Directors		250,000		250,000
Restricted Stock [Member]
Share Based Compensation Arrangement by Share Based Payment Award, Options, Acquired in Period (in shares)	40,753
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount		$ 1,282,000		$ 1,282,000	$ 797,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		1 year 11 months 4 days
Share-based Payment Arrangement, Expense		$ 176,000	$ 199,000
Restricted Stock [Member] \| Director [Member]
Share-based Payment Arrangement, Expense		$ 187,000	$ 205,000
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period (in shares)		6,347	6,082
Restricted Stock [Member] \| Cliff Vested [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Month)		36 months
Restricted Stock [Member] \| Vesting Each Year After Cliff Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage		33.33%
The 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)						675,000