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SECURITIES - Additional Information (Detail) - USD ($) | 6 Months Ended
--- | ---
Jun. 30, 2019 | Jun. 30, 2018
Schedule Of Securities [Line Items] |  |
Gross gains | $ 0 | $ 0
Gross losses | 0 | 0
Other than temporary impairment losses, investments, debt available-for-sale securities | 0 | $ 0
Municipal bond portfolio, value | $ 1,100,000,000 |
Percentage of formal credit enhancement insurance of municipalities | 64.00% |
Municipal Bonds [Member] | Weighted Average [Member] |  |
Schedule Of Securities [Line Items] |  |
Average holding size of securities in bond portfolio | $ 3,200,000 |
Municipal Bonds [Member] | Credit Concentration Risk [Member] | General Obligation Bonds [Member] | A Rating [Member] | Minimum [Member] |  |
Schedule Of Securities [Line Items] |  |
Percentage of portfolio | 100.00% |
Municipal Bonds [Member] | Credit Concentration Risk [Member] | General Obligation Bonds [Member] | A Rating or Better [Member] |  |
Schedule Of Securities [Line Items] |  |
Percentage of portfolio | 99.00% |
Municipal Bonds [Member] | Geographic Concentration Risk [Member] | Pennsylvania, Ohio and Maryland [Member] |  |
Schedule Of Securities [Line Items] |  |
Percentage of portfolio | 66.00% |

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592 + Details
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- Definition Bonds or similar securities issued by state, city, or local governments or the agencies operated by state, city, or local governments 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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