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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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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Note 7 - Share-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Millions		6 Months Ended	9 Months Ended
	Aug. 04, 2018	Jun. 30, 2023	Sep. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)			5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)			$ 4.42
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 1.2
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 6 months
Stock Appreciation Rights (SARs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 0.3
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 3 months 18 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)			$ 4.58
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		3 years
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 4.1
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			2 years 1 month 6 days
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)			$ 12.04
Performance Shares [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 2.0
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			3 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)			$ 12.56
Outside Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)			10 years
Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	1 year
Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)	3 years
Maximum [Member] \| Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			5 years
Maximum [Member] \| Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)			5 years