INVESTMENT IN HISTORIC TAX CREDIT ENTITY Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Oct. 15, 2014	Mar. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
INVESTMENT IN HISTORIC TAX CREDIT ENTITY
Percentage Of Received Equity Interest	99.00%
Percentage Of Receive Operating Profit And Losses	99.00%
Investment Credit Available To Be Estimated	$ 4,700,000
Other Assets	$ 4,200,000		$ 30,126,000	$ 11,530,000
Investment Tax Credit Percentage		90.00%
Historical Tax Credit On Investment		$ 5,000,000.0
Increase In Equity Investment		$ 4,500,000
Income Related To Distributions From Historic Tax Credit Entity			$ 426,000	$ 210,000	$ 585,000