FAIR VALUE - Fair Value of Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value Inputs Level 3 [Member]
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance	$ 14,590	$ 17,238	$ 19,855
Total gains or (losses) (realized/unrealized):
Included in earnings	(1,641)	(497)	(50)
Included in other comprehensive income	2,403	714	222
Purchases	0	0	500
Principal Repayments And Amortization	(3,525)	(2,865)	(3,289)
Ending balance	11,977	14,590	17,238
Available-for-sale Securities [Member]
Total gains or (losses) (realized/unrealized):
Included in earnings	1,641	497	50
Available-for-sale Securities [Member] \| Fair Value Inputs Level 3 [Member]
Total gains or (losses) (realized/unrealized):
BSPR securities acquired	$ 150	$ 0	$ 0

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Principal repayments and amortization during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

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Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

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-Publisher FASB
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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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