Income Taxes - Effective Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Federal statutory rate									$ 1,574	$ 1,861
State taxes, net									407	393
Other permanent items									91	77
Deferred tax estimate adjustment									99	134
Discrete item									0	3,365
Total expense	$ 639	$ 325	$ 517	$ 690	$ 747	$ 738	$ 627	$ 3,719	$ 2,171	$ 5,830