The average holding size, aggregate value, of the securities in the municipal bond portfolio.

No definition available.

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- Definition

The percentage as of the balance sheet date of municipal bonds that have formal credit enhancement insurance.

+ References

No definition available.

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- Definition

Schedule Of Securities [Line Items]

+ References

No definition available.

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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
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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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- Definition

Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=118954083&loc=SL6284422-111562

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Securities - Additional Information (Detail) - USD ($)	12 Months Ended
Securities - Additional Information (Detail) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule Of Securities [Line Items]
OTTI losses on debt securities	$ 0	$ 0	$ 0
Municipal bond portfolio, value	$ 1,100,000,000
Percentage of formal credit enhancement insurance of municipalities	63.00%
Municipal Bonds \| Weighted Average
Schedule Of Securities [Line Items]
Average holding size of securities in bond portfolio	$ 3,400,000
Municipal Bonds \| Credit Concentration Risk \| General Obligation Bonds \| A Rating \| Minimum
Schedule Of Securities [Line Items]
Percentage of portfolio	100.00%
Municipal Bonds \| Credit Concentration Risk \| General Obligation Bonds \| A Rating or Better
Schedule Of Securities [Line Items]
Percentage of portfolio	99.00%
Municipal Bonds \| Geographic Concentration Risk \| Pennsylvania, Ohio and Maryland
Schedule Of Securities [Line Items]
Percentage of portfolio	66.00%