SECURITIES - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2020	Jan. 01, 2020
Schedule Of Securities [Line Items]
Securities available for sale, allowance for credit losses	$ 0
Securities held to maturity, allowance for credit losses	60,000.00
Municipal bond portfolio, value	$ 1,100,000,000
Percentage of formal credit enhancement insurance of municipalities	63.00%
Securities, held-to-maturity, provision expense	$ 10,000.00
Municipal Bonds [Member] \| Weighted Average [Member]
Schedule Of Securities [Line Items]
Average holding size of securities in bond portfolio	$ 3,500,000
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	65.00%
Available-for-sale Debt Securities [Member]
Schedule Of Securities [Line Items]
Accrued investment income receivable	$ 7,400,000
Municipal Portfolio [Member]
Schedule Of Securities [Line Items]
Securities held to maturity, allowance for credit losses	60,000.00	$ 0
Held-to-maturity Securities [Member]
Schedule Of Securities [Line Items]
Accrued investment income receivable	$ 12,800,000

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

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Debt Securities, Held-to-maturity, Provision Expense

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

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Schedule Of Securities [Line Items]

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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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.

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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