Business Combinations - Fair Value of Assets Received and Liabilities Assumed (Details) - USD ($) $ / shares in Units, $ in Thousands	May 26, 2021	Apr. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Business Combination, Description [Abstract]
Common stock, par value			$ 0.01	$ 0.01
Liabilities
Goodwill			$ 19,168	$ 19,168	$ 1,901
Savoy Bank
Business Combination, Description [Abstract]
Total consideration	$ 65,512
Assets
Cash and due from banks	59,155
Investment securities available-for-sale	239
Loans held for sale	3,883
Loans held for investment	569,251
Premises and equipment, net	234
Core deposit intangible	0
Accrued interest receivable	5,171
Other assets	10,432
Total assets acquired	648,365
Liabilities
Deposits	340,215
Borrowings	258,247
Accrued interest payable	1,050
Other liabilities and accrued expenses	3,817
Total liabilities assumed	603,329
Total Consideration	65,512
Savoy Bank | Fair Value Adjustments
Assets
Cash and due from banks	0
Investment securities available-for-sale	0
Loans held for sale	0
Loans held for investment	8,612
Premises and equipment, net	(22)
Core deposit intangible	490
Accrued interest receivable	(650)
Other assets	(2,925)
Total assets acquired	5,505
Liabilities
Deposits	2,527
Borrowings	301
Accrued interest payable	0
Other liabilities and accrued expenses	(342)
Total liabilities assumed	2,486
Savoy Bank | As Adjusted
Business Combination, Description [Abstract]
Total consideration	65,512
Assets
Cash and due from banks	59,155
Investment securities available-for-sale	239
Loans held for sale	3,883
Loans held for investment	577,863
Premises and equipment, net	212
Core deposit intangible	490
Accrued interest receivable	4,521
Other assets	7,507
Total assets acquired	653,870
Liabilities
Deposits	342,742
Borrowings	258,548
Accrued interest payable	1,050
Other liabilities and accrued expenses	3,475
Total liabilities assumed	605,815
Net assets acquired	48,055
Total Consideration	65,512
Goodwill	$ 17,457
Savoy Bank | Common Stock
Business Combination, Description [Abstract]
Common stock, par value		$ 1.00
Business Combination, Cash Paid Per Share		$ 3.246
Conversion of Stock, Shares Issued Per Share		0.141
Total consideration		$ 65,500
Business Acquisition, Share Price		$ 6.49
Liabilities
Total Consideration		$ 65,500