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Securities - Amortized Cost and Fair Value of Debt Securities, by Contractual Maturity (Detail) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018
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Available For Sale Securities Debt Maturities [Abstract] |  |
Amortized Cost, One year or less | $ 45,762 |
Amortized Cost, After one year through five years | 57,593 |
Amortized Cost, After five years through ten years | 54,003 |
Amortized Cost, After ten years | 1,274 |
Amortized Cost, Total | 158,632 |
Amortized Cost, Mortgage-backed securities | 44,763 |
Amortized Cost | 203,395 | $ 172,263
Fair Value, One year or less | 45,744 |
Fair Value, After one year through five years | 57,516 |
Fair Value, After five years through ten years | 55,077 |
Fair Value, After ten years | 1,252 |
Fair Value, Total | 159,589 |
Fair Value, Mortgage-backed securities | 44,826 |
Total, Fair Value | $ 204,415 | $ 168,447

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