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Acquisition of Loans (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Sep. 30, 2018 | Apr. 20, 2018
--- | --- | --- | ---
Business Acquisition [Line Items] |  |  |
Fair Value | $ 9,135 | $ 10,887 |
PCI | GCFC/ABC Bank |  |  |
Business Acquisition [Line Items] |  |  |
Fair Value | 9,403 |  | $ 11,360
Contractually required principal and interest payments | 15,083 |  | 19,447
Best estimate of contractual cash flows not expected to be collected | 4,893 |  | 6,537
Best estimate of contractual cash flows expected to be collected | 10,190 |  | 12,910
Non-PCI | GCFC/ABC Bank |  |  |
Business Acquisition [Line Items] |  |  |
Fair Value | 134,536 |  | 216,234
Contractually required principal and interest payments | 135,822 |  | 220,308
Best estimate of contractual cash flows not expected to be collected | 614 |  | 2,511
Best estimate of contractual cash flows expected to be collected | $ 135,208 |  | $ 217,797

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