Revenue Recognition (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 52,246	$ 55,852	$ 66,871
Noninterest income within the scope of other GAAP Topics	(52,229)	4,880	6,738
Total noninterest income	17	60,732	73,609
Service charges and other fees
Disaggregation of Revenue [Line Items]
Revenue	37,741	43,893	51,077
Wealth management fees
Disaggregation of Revenue [Line Items]
Revenue	11,772	8,914	9,219
Other
Disaggregation of Revenue [Line Items]
Revenue	$ 2,733	$ 3,045	$ 6,575