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Securities - Summary of Amortized Costs and Fair Values of Securities (Detail) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Securities available for sale: |  |  |
Amortized Cost | $ 121,988 | $ 102,147 |
Gross Unrealized Gains | 448 | 75 |
Gross Unrealized (Losses) | (1,234) | (2,365) |
Fair Value | 121,202 | 99,857 |
Securities held to maturity: |  |  |
Amortized Cost | 19,489 | 43,408 |
Gross Unrealized Gains | 35 | 29 |
Gross Unrealized (Losses) | (334) | (1,043) |
Fair Value | 19,190 | 42,394 | [1]
Total securities, Amortized cost | 141,477 | 145,555 |
Total securities, Gross unrealized gains | 483 | 104 |
Total securities, Gross unrealized (losses) | (1,568) | (3,408) |
Total securities, Fair value | 140,392 | 142,251 |
U.S. agency and mortgage-backed securities |  |  |
Securities available for sale: |  |  |
Amortized Cost | 96,345 | 86,944 |
Gross Unrealized Gains | 295 | 44 |
Gross Unrealized (Losses) | (1,074) | (2,066) |
Fair Value | 95,566 | 84,922 |
Securities held to maturity: |  |  |
Amortized Cost | 14,193 | 27,420 |
Gross Unrealized Gains | 0 | 0 |
Gross Unrealized (Losses) | (332) | (869) |
Fair Value | 13,861 | 26,551 |
Obligations of states and political subdivisions |  |  |
Securities available for sale: |  |  |
Amortized Cost | 25,643 | 15,203 |
Gross Unrealized Gains | 153 | 31 |
Gross Unrealized (Losses) | (160) | (299) |
Fair Value | 25,636 | 14,935 |
Securities held to maturity: |  |  |
Amortized Cost | 3,796 | 14,488 |
Gross Unrealized Gains | 22 | 20 |
Gross Unrealized (Losses) | (2) | (174) |
Fair Value | 3,816 | 14,334 |
Corporate debt securities |  |  |
Securities held to maturity: |  |  |
Amortized Cost | 1,500 | 1,500 |
Gross Unrealized Gains | 13 | 9 |
Gross Unrealized (Losses) | 0 | 0 |
Fair Value | $ 1,513 | $ 1,509 |
[1] | Derived from audited consolidated financial statements.

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