ALLOWANCE FOR CREDIT LOSSES FOR LOANS AND FINANCE LEASES - Activity in ACL on Loans and Finance Leases (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	$ 243,942	$ 261,843
Provision for credit losses - (benefit) expense	24,837	12,917
Charge-offs	(28,210)	(29,339)
Recoveries	6,700	18,171
Ending balance	247,269	263,592
Residential Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	40,654	57,397
Provision for credit losses - (benefit) expense	1,004	(464)
Charge-offs	(235)	(516)
Recoveries	217	272
Ending balance	41,640	56,689
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	3,824	5,605
Provision for credit losses - (benefit) expense	(421)	571
Charge-offs	0	0
Recoveries	14	10
Ending balance	3,417	6,186
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	22,447	32,631
Provision for credit losses - (benefit) expense	1,656	(10)
Charge-offs	0	0
Recoveries	40	40
Ending balance	24,143	32,661
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	33,034	33,996
Provision for credit losses - (benefit) expense	3,353	(3,160)
Charge-offs	(77)	(532)
Recoveries	154	5,119
Ending balance	36,464	35,423
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	143,983	132,214
Provision for credit losses - (benefit) expense	19,245	15,980
Charge-offs	(27,898)	(28,291)
Recoveries	6,275	12,730
Ending balance	141,605	132,633
Consumer Portfolio Segment [Member] \| Bulk Sale Of Fully Charged-Off Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Recoveries	$ 2,400	$ 9,500

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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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- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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