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MARKETABLE SECURITIES (Tables) | 6 Months Ended
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Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract] |
Schedule of Amortized Cost and Fair Value of Available for Sale and Held to Maturity Securities | The following tables summarize the amortized cost and fair value of securities available for sale and securities held to maturity as of June 30, 2018 and December 31, 2017 and the corresponding amounts of gross unrealized gains and losses:
June 30, 2018 | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Estimated Fair Value
Available for sale: |  |  |  |  |  |  |
Corporate bonds | $ | 18,784 |  |  | $ | — |  |  | $ | 643 |  |  | $ | 18,141 |
Municipal securities | 18,211 |  |  | 48 |  |  | 305 |  |  | 17,954 |
Mortgage-backed securities | 95,062 |  |  | — |  |  | 3,820 |  |  | 91,242 |
Collateralized mortgage obligations | 119,371 |  |  | — |  |  | 3,218 |  |  | 116,153 |
Total available for sale | $ | 251,428 |  |  | $ | 48 |  |  | $ | 7,986 |  |  | $ | 243,490 |
Held to maturity: |  |  |  |  |  |  |
Municipal securities | $ | 143,295 |  |  | $ | 1,041 |  |  | $ | 1,481 |  |  | $ | 142,855 |
Mortgage-backed securities | 18,880 |  |  | 88 |  |  | 472 |  |  | 18,496 |
Collateralized mortgage obligations | 5,064 |  |  | 61 |  |  | 35 |  |  | 5,090 |
Total held to maturity | $ | 167,239 |  |  | $ | 1,190 |  |  | $ | 1,988 |  |  | $ | 166,441 |
December 31, 2017 | Amortized Cost |  | Gross Unrealized Gains |  | Gross Unrealized Losses |  | Estimated Fair Value
Available for sale: |  |  |  |  |  |  |
Corporate bonds | $ | 18,823 |  |  | $ | 64 |  |  | $ | 50 |  |  | $ | 18,837 |
Municipal securities | 7,746 |  |  | — |  |  | 200 |  |  | 7,546 |
Mortgage-backed securities | 92,471 |  |  | — |  |  | 1,793 |  |  | 90,678 |
Collateralized mortgage obligations | 116,809 |  |  | 5 |  |  | 1,503 |  |  | 115,311 |
Total available for sale | $ | 235,849 |  |  | $ | 69 |  |  | $ | 3,546 |  |  | $ | 232,372 |
Held to maturity: |  |  |  |  |  |  |
Municipal securities | $ | 146,496 |  |  | $ | 2,244 |  |  | $ | 218 |  |  | $ | 148,522 |
Mortgage-backed securities | 22,026 |  |  | 199 |  |  | 230 |  |  | 21,995 |
Collateralized mortgage obligations | 6,162 |  |  | 111 |  |  | — |  |  | 6,273 |
Total held to maturity | $ | 174,684 |  |  | $ | 2,554 |  |  | $ | 448 |  |  | $ | 176,790 |
Schedule of Securities with Gross Unrealized Losses | Information pertaining to securities with gross unrealized losses as of June 30, 2018 and December 31, 2017 aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position is detailed in the following tables:
| Less Than 12 Months |  | 12 Months or Longer |  | Total
June 30, 2018 | Gross Unrealized Losses |  | Estimated Fair Value |  | Gross Unrealized Losses |  | Estimated Fair Value |  | Gross Unrealized Losses |  | Estimated Fair Value
Available for sale: |  |  |  |  |  |  |  |  |  |  |
Corporate bonds | $ | (643 | ) |  | $ | 18,141 |  |  | $ | — |  |  | $ | — |  |  | $ | (643 | ) |  | $ | 18,141 |
Municipal securities | (17 | ) |  | 807 |  |  | (288 | ) |  | 7,410 |  |  | (305 | ) |  | 8,217 |
Mortgage-backed securities | (314 | ) |  | 16,151 |  |  | (3,506 | ) |  | 75,091 |  |  | (3,820 | ) |  | 91,242 |
Collateralized mortgage obligations | (2,504 | ) |  | 91,904 |  |  | (714 | ) |  | 23,847 |  |  | (3,218 | ) |  | 115,751 |
Total available for sale | $ | (3,478 | ) |  | $ | 127,003 |  |  | $ | (4,508 | ) |  | $ | 106,348 |  |  | $ | (7,986 | ) |  | $ | 233,351 |
Held to maturity: |  |  |  |  |  |  |  |  |  |  |
Municipal securities | $ | (952 | ) |  | $ | 68,662 |  |  | $ | (529 | ) |  | $ | 19,466 |  |  | $ | (1,481 | ) |  | $ | 88,128 |
Mortgage-backed securities | (158 | ) |  | 6,686 |  |  | (314 | ) |  | 8,538 |  |  | (472 | ) |  | 15,224 |
Collateralized mortgage obligations | (35 | ) |  | 2,594 |  |  | — |  |  | — |  |  | (35 | ) |  | 2,594 |
Total held to maturity | $ | (1,145 | ) |  | $ | 77,942 |  |  | $ | (843 | ) |  | $ | 28,004 |  |  | $ | (1,988 | ) |  | $ | 105,946 |
| Less Than 12 Months |  | 12 Months or Longer |  | Total
December 31, 2017 | Gross Unrealized Losses |  | Estimated Fair Value |  | Gross Unrealized Losses |  | Estimated Fair Value |  | Gross Unrealized Losses |  | Estimated Fair Value
Available for sale: |  |  |  |  |  |  |  |  |  |  |
Corporate bonds | $ | (50 | ) |  | $ | 8,019 |  |  | $ | — |  |  | $ | — |  |  | $ | (50 | ) |  | $ | 8,019 |
Municipal securities | — |  |  | — |  |  | (200 | ) |  | 7,546 |  |  | (200 | ) |  | 7,546 |
Mortgage-backed securities | (658 | ) |  | 42,881 |  |  | (1,135 | ) |  | 47,797 |  |  | (1,793 | ) |  | 90,678 |
Collateralized mortgage obligations | (1,091 | ) |  | 93,584 |  |  | (412 | ) |  | 21,258 |  |  | (1,503 | ) |  | 114,842 |
Total available for sale | $ | (1,799 | ) |  | $ | 144,484 |  |  | $ | (1,747 | ) |  | $ | 76,601 |  |  | $ | (3,546 | ) |  | $ | 221,085 |
Held to maturity: |  |  |  |  |  |  |  |  |  |  |
Municipal securities | $ | (37 | ) |  | $ | 9,230 |  |  | $ | (181 | ) |  | $ | 19,961 |  |  | $ | (218 | ) |  | $ | 29,191 |
Mortgage-backed securities | (57 | ) |  | 6,499 |  |  | (173 | ) |  | 9,747 |  |  | (230 | ) |  | 16,246 |
Collateralized mortgage obligations | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Total held to maturity | $ | (94 | ) |  | $ | 15,729 |  |  | $ | (354 | ) |  | $ | 29,708 |  |  | $ | (448 | ) |  | $ | 45,437 |
Schedule of Proceeds from Sales of Securities | The proceeds from sales of available for sale securities and the associated gains and losses are listed below for:
| Three Months Ended June 30, |  | Six Months Ended June 30,
| 2018 |  | 2017 |  | 2018 |  | 2017
Proceeds from sales | $ | 9,457 |  |  | $ | 14,762 |  |  | $ | 9,457 |  |  | $ | 14,762 |
Gross gains | — |  |  | 38 |  |  | — |  |  | 38 |
Gross losses | (51 | ) |  | (13 | ) |  | (51 | ) |  | (13 | )
Schedule of Sale of Held To Maturity Securities | Sale of securities held to maturity were as follows for:
| Three Months Ended June 30, | Six Months Ended June 30,
| 2017 |  | 2017
Proceeds from sales | $ | 923 |  |  | $ | 923 |
Amortized cost | 907 |  |  | 907 |
Gross realized gains | 16 |  |  | 16 |
Tax expense related to securities gains/losses | (4 | ) |  | (4 | )
Investments Classified by Contractual Maturity Date | The contractual maturities at June 30, 2018 of available for sale and held to maturity securities at carrying value and estimated fair value are shown below. The Company invests in mortgage-backed securities and collateralized mortgage obligations that have expected maturities that differ from their contractual maturities. These differences arise because borrowers and/or issuers may have the right to call or prepay their obligation with or without call or prepayment penalties.
| Available for Sale |  | Held to Maturity
June 30, 2018 | Amortized Cost |  | Estimated Fair Value |  | Amortized Cost |  | Estimated Fair Value
Due within one year | $ | — |  |  | $ | — |  |  | $ | 1,175 |  |  | $ | 1,175 |
Due after one year through five years | 7,373 |  |  | 7,216 |  |  | 19,089 |  |  | 19,295 |
Due after five years through ten years | 21,924 |  |  | 21,469 |  |  | 40,520 |  |  | 41,178 |
Due after ten years | 7,698 |  |  | 7,410 |  |  | 82,511 |  |  | 81,207 |
Mortgage-backed securities | 95,062 |  |  | 91,242 |  |  | 18,880 |  |  | 18,496 |
Collateralized mortgage obligations | 119,371 |  |  | 116,153 |  |  | 5,064 |  |  | 5,090 |
Total Securities | $ | 251,428 |  |  | $ | 243,490 |  |  | $ | 167,239 |  |  | $ | 166,441 |

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