LOANS AND ALLOWANCE FOR CREDIT LOSSES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Interest income on nonaccrual loans	$ 0	$ 0
Loans, net of unearned income	20,706,644		$ 20,739,906
Unfunded commitments	17,127	$ 4,053
Financing receivable, moody's baseline scenario was weighted percentage			75.00%
Financing receivable, moody's upside scenario in weighted percentage			25.00%
Unfunded Loan Commitments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Modified loans	2,000		$ 179
9
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, net of unearned income	0		0
Loan Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest receivable	$ 73,400		$ 77,300

Financing Receivable, Allowance For Credit Losses On Loans Moody's Baseline Scenario In Weighted Percentage

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Financing Receivable, Allowance For Credit Losses On Loans Moody's Upside Scenario In Weighted Percentage

+ References

No definition available.

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
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-Publisher FASB
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Amount, before allowance for credit loss, of accrued interest on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Accumulated amortized cost excluding accrued interest, of financing receivable modified for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 42
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Amount of interest income on financing receivable on nonaccrual status.

+ References

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