Fair Value Measurements - Significant Inputs Utilized in Cash Flow Models (Details) - Significant Unobservable Inputs (Level 3)	Sep. 30, 2022 Y	Sep. 30, 2021 Y
Discount Rate | Minimum
Fair Value Hierarchy
Servicing rights, measurement input	0.120	0.120
Discount Rate | Minimum | SBA Loans
Fair Value Hierarchy
Servicing rights, measurement input	0.0578	0.0464
Discount Rate | Maximum
Fair Value Hierarchy
Servicing rights, measurement input	0.145	0.145
Discount Rate | Maximum | SBA Loans
Fair Value Hierarchy
Servicing rights, measurement input	0.2672	0.2181
Prepayment Rate
Fair Value Hierarchy
Servicing rights, measurement input	0.2625
Prepayment Rate | Minimum
Fair Value Hierarchy
Servicing rights, measurement input		0.2418
Prepayment Rate | Minimum | SBA Loans
Fair Value Hierarchy
Servicing rights, measurement input	0.0842	0.1187
Prepayment Rate | Maximum
Fair Value Hierarchy
Servicing rights, measurement input		0.2433
Prepayment Rate | Maximum | SBA Loans
Fair Value Hierarchy
Servicing rights, measurement input	0.2400	0.2626
Weighted Average Life | Minimum
Fair Value Hierarchy
Servicing rights, measurement input	1.2	1.96
Weighted Average Life | Minimum | SBA Loans
Fair Value Hierarchy
Servicing rights, measurement input	1.47	0.39
Weighted Average Life | Maximum
Fair Value Hierarchy
Servicing rights, measurement input	3.0	3.3
Weighted Average Life | Maximum | SBA Loans
Fair Value Hierarchy
Servicing rights, measurement input	5.79	5.85