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Investment Securities (Narrative) (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2015 USD ($) security | Sep. 30, 2015 USD ($) security | Sep. 30, 2014 USD ($) | Dec. 31, 2014 USD ($) security
Investment Securities [Abstract] |  |  |  |
Securities pledged as collateral | $ 810,600 | $ 810,600 |  |
Securities transferred from available for sale to held to maturity (at fair value) |  | $ 165,238 | $ 12,802 |
Unrealized holding losses included in accumulated other comprehensive income and in the carrying value of the held to maturity securities | $ 1,100 |  |  |
Number of security positions, unrealized loss position | security | 82 | 82 |  | 122
Number of security positions, unrealized loss position for more than 12 months | security | 10 | 10 |  | 51
Fair value, continuous unrealized loss position for more than 12 months | $ 36,408 | $ 36,408 |  | $ 207,942
Securities available for sale, 12 months or longer, Unrealized Losses | $ 123 | $ 123 |  | $ 5,699
Number of security positions, unrealized loss position for less than 12 months | security | 72 | 72 |  | 71
Securities, less than 12 months, Fair Value | $ 126,105 | $ 126,105 |  | $ 69,888
Securities, less than 12 months, Unrealized Losses | $ 973 | $ 973 |  | $ 236

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- Definition Disclosure regarding factors used to determine that the impairment of securities not categorized as either held-to-maturity securities or trading securities (hence equal to available for sale securities) where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the available-for-sale investments determined to be temporarily impaired for twelve months or longer. + References No definition available. + Details
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