Income Taxes - Schedule of Reconciliation of Actual Income Taxes to Income Taxes at Expected United States Federal Corporate Income Tax Rate (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Federal statutory rate	35.00%	21.00%	24.30%	34.00%
Tax (benefit) expense at the federal statutory rate		$ (784)	$ 1,342	$ 3,340
Effect of permanent book-tax differences		272	75	340
State tax provision		31	76	100
Valuation allowance for net deferred tax assets		1,682	617	(1,610)
Uncertain tax items		74	(3,013)	350
Tax rate differential		150	1,107	(776)
Other items		5	16	0
Total provision		$ 1,430	$ 220	$ 1,744