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Investment Securities - Additional Information (Detail) $ in Millions | Mar. 31, 2019 USD ($) Security | Dec. 31, 2018 USD ($)
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Investments, Debt and Equity Securities [Abstract] |  |
Number of available-for-sale investment securities in the less than twelve month category | 4 |
Number of available-for-sale investment securities in the twelve month category | 22 |
Pledged investment securities fair value | $ | $ 22.9 | $ 23.0

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- Definition Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement. + References No definition available. + Details
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- Definition Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months. + References No definition available. + Details
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- References No definition available. + 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://fasb.org/us-gaap/role/ref/legacyRef -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=109249958&loc=SL6224234-111729 + Details
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Balance Type: | debit
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