Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] |
The amortized cost and fair value of available-for-sale and held-to-maturity securities at March 31, 2018 and December 31, 2017 are summarized as follows: | | Amortized Cost | | Gross Unrealized Gain | | Gross Unrealized Loss | | Fair Value | March 31, 2018 | | | Available for sale debt securities | | | | | | | | | | | | | | | | | U.S. Treasury and government sponsored agencies | | $ | 58,025 | | | $ | 5 | | | $ | (777 | ) | | $ | 57,252 | | Mortgage-backed securities | | | 294,582 | | | | 609 | | | | (6,874 | ) | | | 288,318 | | State and municipal securities | | | 123,123 | | | | 522 | | | | (856 | ) | | | 122,789 | | Corporate debt | | | 91,409 | | | | 1,376 | | | | (509 | ) | | | 92,276 | | Total | | $ | 567,139 | | | $ | 2,512 | | | $ | (9,016 | ) | | $ | 560,635 | | Held to maturity debt securities | | | | | | | | | | | | | | | | | State and municipal securities | | $ | 250 | | | $ | - | | | $ | - | | | $ | 250 | | Total | | $ | 250 | | | $ | - | | | $ | - | | | $ | 250 | | | | | | | | | | | | | | | | | | | December 31, 2017 | | | | | | | | | | | | | | | | | Available for sale debt securities | | | | | | | | | | | | | | | | | U.S. Treasury and government sponsored agencies | | $ | 55,567 | | | $ | 38 | | | $ | (249 | ) | | $ | 55,356 | | Mortgage-backed securities | | | 278,177 | | | | 1,006 | | | | (2,685 | ) | | | 276,498 | | State and municipal securities | | | 134,641 | | | | 761 | | | | (553 | ) | | | 134,849 | | Corporate debt | | | 69,996 | | | | 1,416 | | | | (35 | ) | | | 71,377 | | Total | | $ | 538,381 | | | $ | 3,221 | | | $ | (3,522 | ) | | $ | 538,080 | | Held to maturity debt securities | | | | | | | | | | | | | | | | | State and municipal securities | | $ | 250 | | | $ | - | | | $ | - | | | $ | 250 | | Total | | $ | 250 | | | $ | - | | | $ | - | | | $ | 250 | | The amortized cost and fair value of debt securities as of March 31, 2018 and December 31, 2017 by contractual maturity are shown below. Actual maturities may differ from contractual maturities of mortgage-backed securities since the mortgages underlying the securities may be called or prepaid with or without penalty. Therefore, these securities are not included in the maturity categories along with the other categories of debt securities. | | March 31, 2018 | | December 31, 2017 | | | Amortized Cost | | Fair Value | | Amortized Cost | | Fair Value | | | (In thousands) | Available for sale debt securities | | | | | | | | | | | | | | | | | Due within one year | | $ | 45,864 | | | $ | 45,909 | | | $ | 22,122 | | | $ | 22,172 | | Due from one to five years | | | 194,445 | | | | 193,930 | | | | 160,773 | | | | 160,563 | | Due from five to ten years | | | 29,371 | | | | 29,472 | | | | 73,362 | | | | 74,684 | | Due after ten years | | | 2,877 | | | | 3,006 | | | | 3,947 | | | | 4,163 | | Mortgage-backed securities | | | 294,582 | | | | 288,318 | | | | 278,177 | | | | 276,498 | | | | $ | 567,139 | | | $ | 560,635 | | | $ | 538,381 | | | $ | 538,080 | | | | | | | | | | | | | | | | | | | Held to maturity debt securities | | | | | | | | | | | | | | | | | Due from one to five years | | $ | 250 | | | $ | 250 | | | $ | 250 | | | $ | 250 | | | | $ | 250 | | | $ | 250 | | | $ | 250 | | | $ | 250 | |
All mortgage-backed securities are with government-sponsored enterprises (GSEs) such as Federal National Mortgage Association, Government National Mortgage Association, Federal Home Loan Bank, and Federal Home Loan Mortgage Corporation. The following table identifies, as of March 31, 2018 and December 31, 2017, the Company’s investment securities that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for 12 or more months. At March 31, 2018,
73 of the Company’s 797 debt securities had been in an unrealized loss position for 12 or more months. The Company does not intend to sell these securities, and it is more likely than not that the Company will not be required to sell the securities before recovery of their amortized cost, which may be maturity; accordingly, the Company does not consider these securities to be other-than-temporarily impaired at March 31, 2018. Further, the Company believes any deterioration in value of its current investment securities is attributable to changes in market interest rates and not credit quality of the issuer. | | Less Than Twelve Months | | Twelve Months or More | | Total | | | Gross | | | | Gross | | | | Gross | | | | | Unrealized | | | | Unrealized | | | | Unrealized | | | | | Losses | | Fair Value | | Losses | | Fair Value | | Losses | | Fair Value | | | (In Thousands) | March 31, 2018: | | | | | | | | | | | | | | | | | | | | | | | | | U.S. Treasury and government sponsored agencies | | $ | (635 | ) | | $ | 54,191 | | | $ | (142 | ) | | $ | 2,881 | | | $ | (777 | ) | | $ | 57,072 | | Mortgage-backed securities | | | (4,046 | ) | | | 200,071 | | | | (2,828 | ) | | | 71,042 | | | | (6,874 | ) | | | 271,113 | | State and municipal securities | | | (716 | ) | | | 64,676 | | | | (140 | ) | | | 6,642 | | | | (856 | ) | | | 71,318 | | Corporate debt | | | (509 | ) | | | 26,389 | | | | - | | | | - | | | | (509 | ) | | | 26,389 | | Total | | $ | (5,906 | ) | | $ | 345,327 | | | $ | (3,110 | ) | | $ | 80,565 | | | $ | (9,016 | ) | | $ | 425,892 | | | | | | | | | | | | | | | | | | | | | | | | | | | December 31, 2017: | | | | | | | | | | | | | | | | | | | | | | | | | U.S. Treasury and government sponsored agencies | | $ | (151 | ) | | $ | 33,401 | | | $ | (98 | ) | | $ | 2,926 | | | $ | (249 | ) | | $ | 36,327 | | Mortgage-backed securities | | | (986 | ) | | | 140,432 | | | | (1,699 | ) | | | 75,903 | | | | (2,685 | ) | | | 216,335 | | State and municipal securities | | | (450 | ) | | | 66,637 | | | | (103 | ) | | | 6,648 | | | | (553 | ) | | | 73,285 | | Corporate debt | | | (35 | ) | | | 6,955 | | | | - | | | | - | | | | (35 | ) | | | 6,955 | | Total | | $ | (1,622 | ) | | $ | 247,425 | | | $ | (1,900 | ) | | $ | 85,477 | | | $ | (3,522 | ) | | $ | 332,902 | |
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