BORROWINGS - Additional Information (Details)	Dec. 31, 2021 USD ($) bank	Dec. 31, 2020 USD ($) bank	Aug. 02, 2019 USD ($)
Debt Instrument [Line Items]
Residential real estate loans and securities pledged as collateral for FHLB advances, carrying value	$ 478,400,000	$ 611,200,000
FHLB stock	10,400,000	10,400,000
FHLB borrowing capacity, authorized	800,000,000.0
Current borrowing capacity	227,800,000
Commercial loans pledged as collateral for federal reserve discount window	804,400,000	557,200,000
Federal reserve borrowing capacity	616,500,000	490,400,000
Remaining borrowing capacity	$ 350,000,000.0	$ 350,000,000.0
Number of banks \| bank	11	11
Outstanding borrowings	$ 0	$ 10,500,000
American Financial Exchange
Debt Instrument [Line Items]
Remaining borrowing capacity	319,000,000.0	394,000,000.0
Outstanding borrowings	0	0
Unsecured revolving credit agreement
Debt Instrument [Line Items]
Borrowing capacity			$ 30,000,000.0
Outstanding borrowings	$ 0	$ 10,500,000

The amount authorized to borrow from the Federal Home Loan Bank.

No definition available.

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- Definition

The amount authorized to borrow from the Federal Reserve Bank.

+ References

No definition available.

+ Details

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- Definition

Line Of Credit Facility, Remaining Borrowing Capacity, Number of Banks

+ References

No definition available.

+ Details

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- Definition

The carrying amount as of the date of the latest financial statement presented of commercial loans which are owned but transferred to the Federal Reserve to serve as collateral to partially or fully secure a debt obligation and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

+ References

No definition available.

+ Details

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- Definition

The carrying amount as of the date of the latest financial statement presented of residential mortgage loans and mortgage-related securities classified as available for sale which are owned but transferred to the FHLB to serve as collateral to partially or fully secure a debt obligation and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party.

+ References

No definition available.

+ Details

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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

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=123599499&loc=d3e63345-112809

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ 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
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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