Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
The provision for income taxes differs from the amount of income tax determined by applying statutory federal income tax rates to pretax income
Tax expense at statutory rate	$ 1,619	$ 1,299
State income taxes, net of federal	409	216
Deferred tax adjustment - related to the Tax Act	338	0
Tax exempt interest	(198)	(229)
Other	158	37
Total	$ 2,326	$ 1,323
Tax expense at statutory rate in percent	24.50%	34.00%
State income taxes, net of federal in percent	6.20%	5.64%
Deferred tax adjustment - related to the Tax Act in percent	5.11%	0.00%
Tax exempt interest in percent	3.00%	5.98%
Other in percent	2.38%	0.96%
Total in percent	35.19%	34.62%