Earnings Per Share Data - Additional Information (Detail) - shares	3 Months Ended	6 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Exercisable stock options, included in the diluted earnings per share calculation		252,000		252,000
Effect of dilutive stock options	0	133,000	0	129,000
2009 Plan
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			0
Number of shares, options outstanding	0		0
Inclusive Of Diluted Earning [Member]
Anti-dilutive shares	0	0	0	0

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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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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