INVESTMENTS (Narrative) (Detail) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Schedule of Investments [Line Items]
Net unrealized gains (losses) on available-for-sale securities, net of tax	$ 7,484,000		$ 7,484,000		$ (17,826,000)
Deferred tax assets, unrealized losses on available for sale securities	$ 2,000,000		$ 2,000,000		$ 4,900,000
Unrealized Loss as a Percent of Fair Value	1.00%		1.00%		3.00%
Security pledged as collateral, amortized cost	$ 704,600,000		$ 704,600,000		$ 734,100,000
Security pledged as collateral, fair value	711,500,000		711,500,000		$ 714,400,000
Unrealized loss, change in fair value of bank stock equity securities	$ (22,000)	$ 11,000	$ 62,000	$ (13,000)
Investment Securities Sold, Carrying Amount		441,000		441,000
Gain (Loss) on Sale of Other Investments, Miscellaneous		$ 939,000		$ 939,000

Gain (Loss) on Sale of Other Investments, Miscellaneous

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Investment Securities Sold, Carrying Amount

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Security Owned and Pledged as Collateral, Amortized Cost

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Unrealized Loss as a Percent of Fair Value

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Accumulated unrealized gain (loss), after tax, 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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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from unrealized losses on available-for-sale securities.

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Amount of unrealized gain (loss) on investment in marketable security.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

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