Property and Equipment - Property and Equipment (Detail) - USD ($)	Sep. 30, 2020	Sep. 30, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 33,175,000	$ 31,594,000
Less: Accumulated depreciation and amortization	(24,834,000)	(23,205,000)
Property and equipment, net	8,341,000	8,389,000
Land and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,323,000	3,323,000
Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	13,547,000	13,462,000
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 16,305,000	$ 14,809,000