ALLOWANCE FOR CREDIT LOSSES FOR LOANS AND FINANCE LEASES - Activity in ACL on loans and finance leases (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	$ 254,532	$ 267,058	$ 261,843	$ 260,464
Provision for credit losses - (benefit) expense	16,470	10,643	41,317	47,669
Charge-offs	(29,045)	(20,259)	(84,798)	(62,260)
Recoveries	5,039	6,173	28,634	15,626
Ending balance	246,996	263,615	246,996	263,615
Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance				2,116
Residential Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	46,051	60,514	57,397	62,760
Provision for credit losses - (benefit) expense	(5,476)	(3,349)	(16,533)	(6,776)
Charge-offs	(421)	(499)	(1,428)	(2,628)
Recoveries	497	534	1,215	1,788
Ending balance	40,651	57,200	40,651	57,200
Residential Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance				2,056
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	5,646	4,804	5,605	2,308
Provision for credit losses - (benefit) expense	(1,659)	(642)	(1,642)	1,420
Charge-offs	0	(4)	0	(42)
Recoveries	11	1,463	35	1,935
Ending balance	3,998	5,621	3,998	5,621
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance				0
Commercial Portfolio Segment [Member] \| Mortgage loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	30,078	42,427	32,631	35,064
Provision for credit losses - (benefit) expense	(5,914)	(1,344)	(8,900)	5,901
Charge-offs	0	(1)	0	(107)
Recoveries	41	75	474	299
Ending balance	24,205	41,157	24,205	41,157
Commercial Portfolio Segment [Member] \| Mortgage loans [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance				0
Commercial Portfolio Segment [Member] \| Commercial and Industrial loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	34,448	28,014	33,190	32,906
Provision for credit losses - (benefit) expense	1,138	1,931	(2,890)	3,278
Charge-offs	(1,350)	(9)	(2,141)	(6,477)
Recoveries	210	161	6,287	383
Ending balance	34,446	30,097	34,446	30,097
Commercial Portfolio Segment [Member] \| Commercial and Industrial loans [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance				7
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	138,309	131,299	133,020	127,426
Provision for credit losses - (benefit) expense	28,381	14,047	71,282	43,846
Charge-offs	(27,274)	(19,746)	(81,229)	(53,006)
Recoveries	4,280	3,940	20,623	11,221
Ending balance	$ 143,696	$ 129,540	143,696	129,540
Consumer Portfolio Segment [Member] \| Bulk Sale Of Fully Charged-Off Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Recoveries			$ 10,000
Consumer Portfolio Segment [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance				$ 53

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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- 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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+ 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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