OTHER COMPREHENSIVE LOSS - Reclassifications Out of Accumulated Other Comprehensive Loss (Detail) - Reclassification Out Of Accumulated Other Comprehensive Income [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	$ (5,288)	$ 497	$ (11,749)	$ 497
Reclassification from AOCI, Current Period, Tax	0	0	0	0
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	(5,288)	497	(11,749)	497
Net gain (loss) on investment securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	(5,288)	497	(13,380)	497
Provsion For Credit Losses [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	$ 0	$ 0	$ 1,631	$ 0

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Amount before tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss).

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