ALLOWANCE FOR CREDIT LOSSES FOR LOANS AND FINANCE LEASES - Activity in ACL on Loans and Finance Leases (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	$ 248,578	$ 254,532	$ 243,942	$ 261,843
Provision for credit losses - expense (benefit)	18,270	16,470	63,488	41,317
Charge-offs	(25,185)	(29,045)	(77,924)	(84,798)
Recoveries	5,327	5,039	17,484	28,634
Ending balance	246,990	246,996	246,990	246,996
Residential Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	42,448	46,051	40,654	57,397
Provision for credit losses - expense (benefit)	(2,208)	(5,476)	(411)	(16,533)
Charge-offs	(459)	(421)	(979)	(1,428)
Recoveries	491	497	1,008	1,215
Ending balance	40,272	40,651	40,272	40,651
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	4,551	5,646	3,824	5,605
Provision for credit losses - expense (benefit)	496	(1,659)	1,196	(1,642)
Charge-offs	0	0	0	0
Recoveries	313	11	340	35
Ending balance	5,360	3,998	5,360	3,998
Commercial Portfolio Segment [Member] \| Commercial Mortgage Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	22,746	30,078	22,447	32,631
Provision for credit losses - expense (benefit)	2,503	(5,914)	2,711	(8,900)
Charge-offs	0	0	0	0
Recoveries	117	41	208	474
Ending balance	25,366	24,205	25,366	24,205
Commercial Portfolio Segment [Member] \| Commercial and Industrial Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	39,359	35,440	33,034	33,996
Provision for credit losses - expense (benefit)	(1,397)	885	4,091	(2,871)
Charge-offs	(173)	(1,437)	(316)	(2,317)
Recoveries	65	211	1,045	6,291
Ending balance	37,854	35,099	37,854	35,099
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	139,474	137,317	143,983	132,214
Provision for credit losses - expense (benefit)	18,876	28,634	55,901	71,263
Charge-offs	(24,553)	(27,187)	(76,629)	(81,053)
Recoveries	4,341	4,279	14,883	20,619
Ending balance	138,138	143,043	138,138	143,043
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	$ 2,400	$ 10,000

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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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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+ 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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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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