Represents maximum percentage of common stock available for repurchase

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- Definition

Intrinsic value of exercised award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

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- Definition

Amount of difference between the fair value of the options on the date of exercise less their exercise price. The amount of taxable income to the person who exercised and a deduction to taxable income for the Company.

+ References

No definition available.

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- Definition

Face amount per share of no-par value common stock.

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

+ References

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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.

+ References

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- Definition

Number of non-option equity instruments exercised by participants.

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- Definition

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

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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

+ Details

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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Note 7 - Stock Plans (Details Textual) - USD ($)	3 Months Ended	6 Months Ended		12 Months Ended
Note 7 - Stock Plans (Details Textual) - USD ($)	Jun. 30, 2023	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2015	Dec. 31, 2022
Common Stock, No Par Value (in dollars per share)	$ 0	$ 0			$ 0
Maximum Percentage of Common Stock, Available for Repurchase			3.00%
Treasury Stock, Shares, Acquired (in shares)		32,554
Shares Acquired, Average Cost Per Share (in dollars per share)		$ 38.81
Stock Settled Stock Appreciation Rights SSARs [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Exercised (in shares)		7,665	0
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Exercised		$ 35,370
Share-based Compensation Arrangement by Share-based Payment Award, Non-option, Exercises in Period, Realized Tax Deduction		149,886
Share-Based Payment Arrangement, Expense, Tax Benefit		$ 31,476
The 2022 Stock Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	500,000	500,000
The 2022 Stock Incentive Plan [Member] \| Restricted Stock [Member] \| Vesting Each Year [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage		33.00%
The 2022 Stock Incentive Plan [Member] \| Restricted Stock [Member] \| Award Date Three [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		1 year
The 2022 Stock Incentive Plan [Member] \| Restricted Stock [Member] \| Award Date Two [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		3 years
The 2022 Stock Incentive Plan [Member] \| Restricted Stock [Member] \| Award Date One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			3 years
Long-Term Incentive Plan [Member] \| Stock Settled Stock Appreciation Rights SSARs [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)				10 years
Long-Term Incentive Plan [Member] \| Restricted Stock [Member] \| New Employee [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	1,000
The 2002 Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)	165,000	165,000
Shares, Issued (in shares)	101,827	101,827
The 2012 Director Stock Incentive Plan [Member] \| Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			3 years
The 2012 Director Stock Incentive Plan [Member] \| Restricted Stock [Member] \| Vesting Each Year [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage			33.00%