FAIR VALUE MEASURES - Significant Unobservable Inputs Used in Fair Value Measurement of Level 3 Assets and Liabilities (Details) $ in Thousands	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available for sale, at fair value	$ 1,052,268	$ 592,621
Other real estate owned, at fair value	835	3,810
Fair Value, Measurements, Recurring \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available for sale, at fair value	1,320	1,380
Fair Value, Measurements, Nonrecurring \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Collateral-dependent loans, at fair value	36,033	44,181
Other real estate owned, at fair value	702
Mortgage servicing rights	$ 257,112	$ 206,944
Discounted par values \| Discount rate \| Fair Value, Measurements, Recurring \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available for sale, measurement input	0.13	0.08
Discounted par values \| Discount rate \| Fair Value, Measurements, Recurring \| Weighted Average Daily Balance \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available for sale, measurement input	0.13	0.08
Discounted par values \| Loss Given Default \| Fair Value, Measurements, Recurring \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available for sale, measurement input	0.44
Discounted par values \| Loss Given Default \| Fair Value, Measurements, Recurring \| Weighted Average Daily Balance \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Debt securities available for sale, measurement input	0.44
Third-party appraisals and discounted cash flows \| Collateral discounts and discount rates \| Fair Value, Measurements, Nonrecurring \| Minimum \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Collateral-dependent loans, measurement input	0.00%	0.00%
Third-party appraisals and discounted cash flows \| Collateral discounts and discount rates \| Fair Value, Measurements, Nonrecurring \| Maximum \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Collateral-dependent loans, measurement input	40.00%	50.00%
Third-party appraisals and discounted cash flows \| Collateral discounts and discount rates \| Fair Value, Measurements, Nonrecurring \| Weighted Average Daily Balance \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Collateral-dependent loans, measurement input	31.00%	39.00%
Third-party appraisals and sales contracts \| Collateral discounts and estimated costs to sell \| Fair Value, Measurements, Nonrecurring \| Minimum \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other real estate owned, measurement input	0.15
Third-party appraisals and sales contracts \| Collateral discounts and estimated costs to sell \| Fair Value, Measurements, Nonrecurring \| Maximum \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other real estate owned, measurement input	0.55
Third-party appraisals and sales contracts \| Collateral discounts and estimated costs to sell \| Fair Value, Measurements, Nonrecurring \| Weighted Average Daily Balance \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other real estate owned, measurement input	0.37
Discounted cash flows \| Discount rate \| Fair Value, Measurements, Nonrecurring \| Minimum \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights measurement input	0.10	0.09
Discounted cash flows \| Discount rate \| Fair Value, Measurements, Nonrecurring \| Maximum \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights measurement input	0.11	0.10
Discounted cash flows \| Discount rate \| Fair Value, Measurements, Nonrecurring \| Weighted Average Daily Balance \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights measurement input	0.10	0.09
Discounted cash flows \| Prepayment speed \| Fair Value, Measurements, Nonrecurring \| Minimum \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights measurement input	0.04	0.10
Discounted cash flows \| Prepayment speed \| Fair Value, Measurements, Nonrecurring \| Maximum \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights measurement input	0.22	0.40
Discounted cash flows \| Prepayment speed \| Fair Value, Measurements, Nonrecurring \| Weighted Average Daily Balance \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage servicing rights measurement input	0.08	13

Collateral-Dependent Loans, Measurement Input

No definition available.

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- Definition

Mortgage Servicing Rights

+ References

No definition available.

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- Definition

Mortgage Servicing Rights Measurement Input

+ References

No definition available.

+ Details

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- Definition

Amount of 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 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
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+ Details

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- Definition

Value of input used to measure 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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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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.

+ Details

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- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

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- Definition

Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

+ Details

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5162-111524

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