FAIR VALUE MEASUREMENTS - Recurring Level III Assets (Details) - Level III - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 38,919	$ 35,172
Realized and unrealized gains (losses) included in earnings	(1,657)	(90)
Purchase of securities	22,228	842
Maturities/calls	(15,778)	(15,716)
Reclassification to nonrecurring assets		(300)
Unrealized gain included in other comprehensive income (loss)	7,119	34,702
Unrealized loss included in other comprehensive income (loss)	(7,152)	(15,691)
Ending balance	43,679	38,919
Equity Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	0	300
Realized and unrealized gains (losses) included in earnings	0	0
Purchase of securities	0	0
Maturities/calls	0	0
Reclassification to nonrecurring assets		(300)
Unrealized gain included in other comprehensive income (loss)	0	0
Unrealized loss included in other comprehensive income (loss)	0	0
Ending balance	0	0
Interest rate lock commitment \| Interest Rate Lock Commitments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	1,660	1,750
Realized and unrealized gains (losses) included in earnings	(1,660)	(90)
Purchase of securities	0	0
Maturities/calls	0	0
Reclassification to nonrecurring assets		0
Unrealized gain included in other comprehensive income (loss)	0	0
Unrealized loss included in other comprehensive income (loss)	0	0
Ending balance	0	1,660
Municipal Securities \| Total debt securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	37,259	33,122
Realized and unrealized gains (losses) included in earnings	3	0
Purchase of securities	22,228	842
Maturities/calls	(15,778)	(15,716)
Reclassification to nonrecurring assets		0
Unrealized gain included in other comprehensive income (loss)	7,119	34,702
Unrealized loss included in other comprehensive income (loss)	(7,152)	(15,691)
Ending balance	$ 43,679	$ 37,259

Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers Into Of Level 2

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

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
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of gain (loss) recognized in other comprehensive income (OCI) 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
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- Definition

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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-Publisher FASB
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Amount of settlement 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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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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