Income Taxes - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended			9 Months Ended
	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Tax Disclosure [Abstract]
Income tax expense	$ 3,361		$ 2,608	$ 8,109	$ 8,944
Federal income tax expense	2,467		1,900	5,953	6,578
State income tax expense	$ 894		$ 708	$ 2,156	$ 2,366
Reduction in provision for other adjustments		$ 520
Reduction in provision for other adjustments, impact on diluted earnings per share (in dollars per share)		$ 0.02
Reduction in effective income tax rate	0.00%		0.00%	0.90%	0.00%