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Business Combination and Asset Purchase - Schedule of Future Amortization of Core Deposit Intangible Assets (Detail) $ in Thousands | Sep. 30, 2019 USD ($)
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Business Acquisition [Line Items] |
2019 | $ 727
2020 | 721
2021 | 560
2022 | 560
2023 | 560
2024 | 560
2025 | 560
Total | 4,248
Custar [Member] |
Business Acquisition [Line Items] |
2019 | 167
2020 | 161
Total | 328
Geneva [Member] |
Business Acquisition [Line Items] |
2019 | 560
2020 | 560
2021 | 560
2022 | 560
2023 | 560
2024 | 560
2025 | 560
Total | $ 3,920

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