Net Income Per Share Data - Denominator for Computation of Basic and Diluted Net Income Per Share (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net income available to common shareholders	$ 1,462	$ 1,262	$ 1,610	$ 2,572
Basic weighted average shares outstanding	13,507	13,390	13,474	13,379
Dilutive effect of outstanding stock options, nonvested restricted stock, restricted stock units, deferred stock units and performance shares	244	395	305	437
Diluted weighted average shares outstanding	13,751	13,785	13,779	13,816

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Amount after tax of income (loss) from continuing operations attributable to the parent.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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