INVESTMENT SECURITIES - Additional Information (Details)	3 Months Ended
Mar. 31, 2022 USD ($) security	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Amortized cost basis, transferred from the available-for-sale portfolio to the held-to-maturity portfolio	$ 346,000,000
Available-for-sale securities, accumulated gross unrealized gain (loss), before tax	(16,600,000)
Net unrealized loss on securities transferred from available-for-sale to held-to-maturity	$ 0		$ 0
Securities available for sale portfolio \| security	79		119
Available for sale securities in unrealized loss position \| security	56		46
OTTI recorded	$ 0	$ 0
Collateral Pledged
Debt Securities, Available-for-sale [Line Items]
Securities pledged	28,800,000		$ 28,900,000
Available-for-sale Securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale and held to maturity, accrued interest, after allowance for credit loss	$ 6,000,000		$ 4,700,000

Amortized Cost Basis, Transferred From the Available-for-sale Portfolio to the Held-to-maturity Portfolio

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- Definition

Debt Securities, Available-For-Sale And Held To Maturity, Accrued Interest, After Allowance For Credit Loss

+ References

No definition available.

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- Definition

Number of available for sale securities in portfolio.

+ References

No definition available.

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- Definition

Amount, before tax, of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aaa)
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-Topic 320
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-Section 50
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 210
-Section 45
-Paragraph 4
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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

+ References

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-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=124260329&loc=SL6284422-111562

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- Definition

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.

+ References

No definition available.

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