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Securities (Details 2) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost | $ 3,965 |
Less Than 12 Months |  |
Fair Value | 392,344 | $ 266,768
Unrealized Losses | (9,267) | (2,112)
More Than 12 Months |  |
Fair Value | 243,858 | 222,763
Unrealized Losses | (14,145) | (7,423)
Total |  |
Fair Value | 636,202 | 489,531
Unrealized Losses | (23,412) | (9,535)
US Government Agencies Debt Securities [Member] |  |
Less Than 12 Months |  |
Fair Value | 0 | 9,321
Unrealized Losses | 0 | (86)
More Than 12 Months |  |
Fair Value | 11,782 | 3,538
Unrealized Losses | (571) | (232)
Total |  |
Fair Value | 11,782 | 12,859
Unrealized Losses | (571) | (318)
Mortgage Backed Securities - Residential |  |
Less Than 12 Months |  |
Fair Value | 104,404 | 79,918
Unrealized Losses | (3,323) | (425)
More Than 12 Months |  |
Fair Value | 52,106 | 53,815
Unrealized Losses | (2,823) | (1,387)
Total |  |
Fair Value | 156,510 | 133,733
Unrealized Losses | (6,146) | (1,812)
Collateralized Mortgage Obligations |  |
Less Than 12 Months |  |
Fair Value | 191,204 | 150,182
Unrealized Losses | (4,317) | (1,418)
More Than 12 Months |  |
Fair Value | 158,396 | 146,750
Unrealized Losses | (9,648) | (5,287)
Total |  |
Fair Value | 349,600 | 296,932
Unrealized Losses | (13,965) | (6,705)
State and Municipal Obligations |  |
Less Than 12 Months |  |
Fair Value | 96,736 | 27,347
Unrealized Losses | (1,627) | (183)
More Than 12 Months |  |
Fair Value | 21,574 | 18,660
Unrealized Losses | (1,103) | (517)
Total |  |
Fair Value | 118,310 | 46,007
Unrealized Losses | $ (2,730) | $ (700)

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