SUBORDINATED DEBT - Additional Information (Details) - Subordinated Debt [Member] - USD ($)	1 Months Ended	3 Months Ended
Dec. 31, 2020	Dec. 31, 2017	Jun. 30, 2016	Jun. 30, 2021
Debt Instrument [Line Items]
Principal amount	$ 100,000,000.0	$ 35,000,000.0	$ 50,000,000.0
Non-callable term	5 years	5 years	5 years
Notes maturity date	Dec. 22, 2030	Dec. 15, 2027	Jun. 30, 2026
Fixed interest rate	3.50%	4.75%	6.00%
LIBOR spread	326.00%	2.54%	4.85%
Redemption of debt				$ 50,000,000.0
Debt costs net, written-off				$ 648,000
Debt issuance costs	$ 1,900,000	$ 875,000
Parent Company [Member]
Debt Instrument [Line Items]
Net proceeds used to contribute to the Bank		29,100,000	$ 40,000,000.0
Proceeds from debt retained by parent		$ 5,000,000	$ 10,000,000

Term of non-callable provision of debt.

No definition available.

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- Definition

Net proceeds from debt used for contributions.

+ References

No definition available.

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- Definition

Proceeds from debt retained by parent.

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

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-SubTopic 30
-Section 55
-Paragraph 8
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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