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Investment Securities - Additional Information (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2017 USD ($) security | Jun. 30, 2016 USD ($) | Jun. 30, 2017 USD ($) security | Jun. 30, 2016 USD ($) | Dec. 31, 2016 USD ($) security
Investments Debt And Equity Securities [Abstract] |  |  |  |  |
Securities pledged, carrying amount | $ 380,751,000 |  | $ 380,751,000 |  | $ 390,814,000
Recognized gains on early call of available-for-sale securities |  |  | $ 1,000 |  |
Number of securities in securities portfolio | security | 314 |  | 314 |  | 329
Number of securities in securities portfolio, unrealized loss position | security | 120 |  | 120 |  | 151
Other-than-temporary impairment recorded by the company | $ 0 | $ 0 | $ 0 | $ 0 |

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- Definition Realized gains on early call of available-for-sale securities. + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563 + Details
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- Definition The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 8B -URI http://asc.fasb.org/extlink&oid=73527792&loc=SL6284393-111563 + Details
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- Definition Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729 + Details
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