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Investment Securities - Additional Information (Detail) | 6 Months Ended |
--- | --- | ---
Jun. 30, 2020 USD ($) investment_security | Dec. 31, 2019 USD ($)
Investment Securities [Line Items] |  |
Securities pledged as collateral | $ 479,242,000 | $ 466,321,000
Residential real estate mortgage-backed securities | $ 739,470,000,000 |
Life of mortgage-backed securities | 3 years 3 months 3 days |
Asset backed securities |  |
Investment Securities [Line Items] |  |
Percentage of aggregate depreciation in unrealized losses | (3.58%) |
Number of available for sale securities in unrealized loss position (in investment securities) | investment_security | 13 |

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- Definition Investment Securities [Line Items] + References No definition available. + Details
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- Definition Life of mortgage backed securities. + References No definition available. + Details
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- Definition Percentage of aggregate depreciation in unrealized losses. + References No definition available. + Details
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- Definition Securities Pledged as Collateral + 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 unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922888-210455 + Details
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- Definition Debt securities issued by a United States government agency such as Government National Mortgage Association (Ginnie Mae), Federal Home Loan Mortgage Corporation (Freddie Mac), and Federal National Mortgage Association (Fannie Mae), which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. + References No definition available. + Details
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- Details
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