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Investment Securities - Investment Securities in Unrealized Loss Positions (Details) $ in Thousands | Jun. 30, 2015 USD ($) security | Dec. 31, 2014 USD ($) security
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Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Number of investment securities other-than-temporarily impaired | security | 0 |
Number of investment securities in unrealized loss position | security | 35 | 28
Held-to-maturity, less than 12 continuous months, Fair value | $ 20,247 | $ 8,839
Held-to-maturity, less than 12 continuous months, Unrealized loss | (59) | (28)
Held-to-maturity, greater than 12 continuous months, Fair value | 357 | 3,892
Held-to-maturity, greater than 12 continuous months, Unrealized loss | (13) | (37)
Held-to-maturity, Total Securities in a loss position, Fair value | 20,604 | 12,731
Held-to-maturity, Gross Unrealized Losses | (72) | (65)
Available-for-sale, less than 12 continuous months, Fair value | 49,191 | 27,387
Available-for-sale, less than 12 continuous months, Unrealized loss | (297) | (91)
Available-for-sale, greater than 12 continuous months, Fair value | 16,276 | 18,277
Available-for-sale, greater than 12 continuous months, Unrealized loss | (224) | (340)
Available-for-sale, Total Securities in a loss position, Fair Value | 65,467 | 45,664
Available-for-sale, Total Securities in a loss position, Unrealized loss | (521) | (431)
Marketable securities, less than 12 continuous months, Fair value | 69,438 | 36,226
Marketable securities, less than 12 continuous months, Unrealized loss | (356) | (119)
Marketable securities, greater than 12 continuous months, Fair value | 16,633 | 22,169
Marketable securities, greater than 12 continuous months, Unrealized loss | (237) | (377)
Marketable securities, Total Securities in a loss position, Fair value | 86,071 | 58,395
Marketable securities, Total Securities in a loss position, Unrealized loss | $ (593) | (496)
Number of investment securities in unrealized loss position longer than 12 months | security | 6 |
Number of investment securities in unrealized loss position less than 12 months | security | 29 |
Mortgage-backed Securities, Issued by FHLMC and FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, less than 12 continuous months, Fair value | $ 30,577 | 1,960
Available-for-sale, less than 12 continuous months, Unrealized loss | (194) | (11)
Available-for-sale, greater than 12 continuous months, Fair value | 0 | 0
Available-for-sale, greater than 12 continuous months, Unrealized loss | 0 | 0
Available-for-sale, Total Securities in a loss position, Fair Value | 30,577 | 1,960
Available-for-sale, Total Securities in a loss position, Unrealized loss | (194) | (11)
CMOs issued by FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, less than 12 continuous months, Fair value | 0 | 0
Available-for-sale, less than 12 continuous months, Unrealized loss | 0 | 0
Available-for-sale, greater than 12 continuous months, Fair value | 3,698 | 4,115
Available-for-sale, greater than 12 continuous months, Unrealized loss | (37) | (58)
Available-for-sale, Total Securities in a loss position, Fair Value | 3,698 | 4,115
Available-for-sale, Total Securities in a loss position, Unrealized loss | (37) | (58)
CMOs issued by FHLMC |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, less than 12 continuous months, Fair value | 0 | 17,157
Available-for-sale, less than 12 continuous months, Unrealized loss | 0 | (44)
Available-for-sale, greater than 12 continuous months, Fair value | 2,140 | 2,291
Available-for-sale, greater than 12 continuous months, Unrealized loss | (38) | (43)
Available-for-sale, Total Securities in a loss position, Fair Value | 2,140 | 19,448
Available-for-sale, Total Securities in a loss position, Unrealized loss | (38) | (87)
CMOs issued by GNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, less than 12 continuous months, Fair value | 2,810 | 3,262
Available-for-sale, less than 12 continuous months, Unrealized loss | (8) | (16)
Available-for-sale, greater than 12 continuous months, Fair value | 0 | 0
Available-for-sale, greater than 12 continuous months, Unrealized loss | 0 | 0
Available-for-sale, Total Securities in a loss position, Fair Value | 2,810 | 3,262
Available-for-sale, Total Securities in a loss position, Unrealized loss | (8) | (16)
Debentures of government-sponsored agencies |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, less than 12 continuous months, Fair value | 0 | 494
Available-for-sale, less than 12 continuous months, Unrealized loss | 0 | (1)
Available-for-sale, greater than 12 continuous months, Fair value | 9,853 | 9,769
Available-for-sale, greater than 12 continuous months, Unrealized loss | (147) | (231)
Available-for-sale, Total Securities in a loss position, Fair Value | 9,853 | 10,263
Available-for-sale, Total Securities in a loss position, Unrealized loss | (147) | (232)
Privately-issued CMOs |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, less than 12 continuous months, Fair value | 414 | 817
Available-for-sale, less than 12 continuous months, Unrealized loss | (2) | (15)
Available-for-sale, greater than 12 continuous months, Fair value | 0 | 0
Available-for-sale, greater than 12 continuous months, Unrealized loss | 0 | 0
Available-for-sale, Total Securities in a loss position, Fair Value | 414 | 817
Available-for-sale, Total Securities in a loss position, Unrealized loss | (2) | (15)
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Available-for-sale, less than 12 continuous months, Fair value | 15,390 |
Available-for-sale, less than 12 continuous months, Unrealized loss | (93) |
Available-for-sale, greater than 12 continuous months, Fair value | 585 |
Available-for-sale, greater than 12 continuous months, Unrealized loss | (2) |
Available-for-sale, Total Securities in a loss position, Fair Value | 15,975 |
Available-for-sale, Total Securities in a loss position, Unrealized loss | (95) |
Obligations of state and political subdivisions |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held-to-maturity, less than 12 continuous months, Fair value | 12,348 | 5,830
Held-to-maturity, less than 12 continuous months, Unrealized loss | (47) | (27)
Held-to-maturity, greater than 12 continuous months, Fair value | 357 | 359
Held-to-maturity, greater than 12 continuous months, Unrealized loss | (13) | (13)
Held-to-maturity, Total Securities in a loss position, Fair value | 12,705 | 6,189
Held-to-maturity, Gross Unrealized Losses | (60) | (40)
Available-for-sale, less than 12 continuous months, Fair value |  | 2,695
Available-for-sale, less than 12 continuous months, Unrealized loss |  | (3)
Available-for-sale, greater than 12 continuous months, Fair value |  | 1,112
Available-for-sale, greater than 12 continuous months, Unrealized loss |  | (5)
Available-for-sale, Total Securities in a loss position, Fair Value |  | 3,807
Available-for-sale, Total Securities in a loss position, Unrealized loss |  | (8)
Corporate bonds |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held-to-maturity, less than 12 continuous months, Fair value | 5,543 | 3,009
Held-to-maturity, less than 12 continuous months, Unrealized loss | (5) | (1)
Held-to-maturity, greater than 12 continuous months, Fair value | 0 | 3,533
Held-to-maturity, greater than 12 continuous months, Unrealized loss | 0 | (24)
Held-to-maturity, Total Securities in a loss position, Fair value | 5,543 | 6,542
Held-to-maturity, Gross Unrealized Losses | (5) | (25)
Available-for-sale, less than 12 continuous months, Fair value |  | 1,002
Available-for-sale, less than 12 continuous months, Unrealized loss |  | (1)
Available-for-sale, greater than 12 continuous months, Fair value |  | 990
Available-for-sale, greater than 12 continuous months, Unrealized loss |  | (3)
Available-for-sale, Total Securities in a loss position, Fair Value |  | 1,992
Available-for-sale, Total Securities in a loss position, Unrealized loss |  | (4)
MBS pass-through securities issued by FHLMC and FNMA |  |
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items] |  |
Held-to-maturity, less than 12 continuous months, Fair value | 2,356 |
Held-to-maturity, less than 12 continuous months, Unrealized loss | (7) |
Held-to-maturity, greater than 12 continuous months, Fair value | 0 |
Held-to-maturity, greater than 12 continuous months, Unrealized loss | 0 |
Held-to-maturity, Total Securities in a loss position, Fair value | 2,356 |
Held-to-maturity, Gross Unrealized Losses | $ (7) | $ 0

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