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Investment Securities (Narrative) (Details) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2018 USD ($) Security | Jun. 30, 2017 USD ($) | Dec. 31, 2017 USD ($) Security
Investments [Abstract] |  |  |
Securities pledged as collateral | $ 813,500,000 |  | $ 838,400,000
Number of security positions, unrealized loss position | Security | 563 |  | 411
Number of security positions, unrealized loss position for more than 12 months | Security | 187 |  | 172
Securities, 12 months or longer, Fair Value | $ 268,015,000 |  | $ 274,763,000
Securities, 12 months or longer, Unrealized Losses | $ 12,196,000 |  | $ 7,033,000
Number of security positions, unrealized loss position for less than 12 months | Security | 376 |  | 239
Securities, less than 12 months, Fair Value | $ 499,432,000 |  | $ 433,097,000
Securities, less than 12 months, Unrealized Losses | 14,891,000 |  | $ 3,957,000
Impairment recorded | $ 0 | $ 0 |

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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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- Definition Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563 + Details
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