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Share based compensation arrangement by share based payment award fair value assumptions expected forfeiture rate of unvested outstanding awards.

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Share based compensation arrangement by share based payment award number of shares reserved for issuance under awards outstanding.

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The allocated share based compensation expense net of tax amount per basic and diluted share.

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The percent dividend settlement amount for holders of common stock in a stock split.

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

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Amount, after tax, of expense for award under share-based payment arrangement.

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Face amount or stated value per share of common stock.

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Amount of cost for defined contribution plan.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

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Maximum amount the employee may contribute to a defined contribution plan.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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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.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Net number of non-option equity instruments granted to participants.

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

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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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.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Value, before forfeiture, of shares granted under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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Note 10 - Employee Benefits (Details Textual)			1 Months Ended										12 Months Ended
Note 10 - Employee Benefits (Details Textual)	Aug. 13, 2020 $ / shares shares	May 07, 2019 shares	May 31, 2024 shares	May 31, 2023 shares	Aug. 31, 2022 shares	May 31, 2022 shares	May 31, 2021 shares	May 31, 2020 shares	May 31, 2019 shares	Dec. 31, 2018 shares	Aug. 31, 2018 shares	May 31, 2018 shares	Dec. 31, 2024 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted \| shares													2,781,347
Common Stock, Par or Stated Value Per Share \| $ / shares													$ 0.01	$ 0.01
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Forfeiture Rate Of Unvested Outstanding Awards													1.25%
Share-Based Payment Arrangement, Expense													$ 2,236,000	$ 2,319,000	$ 2,814,000
Share-Based Payment Arrangement, Expense, after Tax													$ 1,700,000	$ 1,700,000	$ 2,200,000
Share Based Compensation Expense Net Of Tax Amount Per Basic Share (in dollars per share) \| $ / shares													$ 0.02	$ 0.02	$ 0.03
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number \| shares													704,421	838,150
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term													3 years 3 months 18 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value													$ 339,000
Exercisable, shares (in shares) \| shares													441,921
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term													2 years 8 months 12 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Intrinsic Value													$ 332,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period, Intrinsic Value													521,000	$ 1,100,000	$ 2,000,000
Proceeds from Stock Options Exercised													1,800,000	2,400,000	4,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested in Period, Fair Value													$ 599,000	744,000	691,000
Defined Contribution Plan, Employer Matching Contribution, Percent of Match													35.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay													6.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage													20.00%
Defined Contribution Plan, Employer Discretionary Contribution Amount													$ 0	0	0
Defined Contribution Plan, Cost													3,400,000	3,900,000	4,000,000
Retirement Savings Plan, Participants Less Than 50 Years Old [Member]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount													23,000
Retirement Savings Plan, Participants Over50 Years Old [Member]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount													$ 30,500
Stock Split To [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	3
Stock Split from [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	2
Stock Split [Member]
Common Stock, Par or Stated Value Per Share \| $ / shares	$ 0.01
Stockholders' Equity Note, Stock Split, Dividend Settlement, Percent	50.00%
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period													5 years
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Reserved For Issuance Under Awards Outstanding \| shares													704,421
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value													$ 901,000
Performance Shares [Member] \| Awards Paid to Employees Upon Vesting [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted \| shares			125,464	114,044	21,000	102,900	98,400	73,205	45,000	3,000	3,000	42,000
Performance Shares [Member] \| One Half of Awards Paid Immediately Upon Vesting and One Half Credited to Employees' Accounts [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted \| shares									60,000
Unvested Service Based Option Awards [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount													$ 1,200,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition													2 years 4 months 24 days
Unvested Performance Unit Awards [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount													$ 4,800,000
Service Based Options [Member]
Shares Granted, Value, Share-Based Payment Arrangement, before Forfeiture													$ 147,000	$ 258,000	$ 819,000
2015 Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized \| shares		1,300,000
2015 Equity Incentive Plan [Member] \| Stock Split [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized \| shares	3,950,000
2015 Equity Incentive Plan [Member] \| Share-Based Payment Arrangement, Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award Annual Percentage Of Award Which Vests													20.00%
2015 Equity Incentive Plan [Member] \| Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Granted \| shares												68,550
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Reserved For Issuance Under Awards Outstanding \| shares													298,791
2015 Equity Incentive Plan [Member] \| Full Value Awards [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized \| shares		558,334
Minimum [Member] \| 2015 Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period													7 years
Maximum [Member] \| 2015 Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period													10 years