Income Taxes - Provision for Income Tax Expense (Detail) - USD ($)	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Current:
Federal	$ 3,430,000	$ 2,297,000
State	346,000	148,000
Total current	3,776,000	2,445,000
Deferred:
Federal	(2,436,000)	52,000
State	(190,000)	131,000
Total deferred	(2,626,000)	183,000
Income tax expense	$ 1,150,000	$ 2,628,000

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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