Income Taxes - Provision for Income Tax Expense (Benefit) (Detail) - USD ($)	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Current:
Federal	$ 4,645,000	$ 4,718,000
State	446,000	335,000
Total current	5,091,000	5,053,000
Deferred:
Federal	(442,000)	609,000
State	(111,000)	510,000
Total deferred	(553,000)	1,119,000
Income tax expense	$ 4,538,000	$ 6,172,000