ALLOWANCE FOR CREDIT LOSSES FOR LOANS AND FINANCE LEASES - Activity in ACL on loans and finance leases (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning balance	$ 263,592	$ 265,567	$ 261,843	$ 260,464
Provision for credit losses - (benefit) expense	11,930	20,770	24,847	37,026
Charge-offs	(26,414)	(24,084)	(55,753)	(42,001)
Recoveries	5,424	4,805	23,595	9,453
Ending balance	254,532	267,058	254,532	267,058
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	56,689	64,403	57,397	62,760
Provision for credit losses - (benefit) expense	(10,593)	(3,500)	(11,057)	(3,427)
Charge-offs	(491)	(1,146)	(1,007)	(2,129)
Recoveries	446	757	718	1,254
Ending balance	46,051	60,514	46,051	60,514
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	6,186	3,231	5,605	2,308
Provision for credit losses - (benefit) expense	(554)	1,202	17	2,062
Charge-offs	0	(38)	0	(38)
Recoveries	14	409	24	472
Ending balance	5,646	4,804	5,646	4,804
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	32,661	36,460	32,631	35,064
Provision for credit losses - (benefit) expense	(2,976)	5,999	(2,986)	7,245
Charge-offs	0	(88)	0	(106)
Recoveries	393	56	433	224
Ending balance	30,078	42,427	30,078	42,427
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	34,490	31,235	33,190	32,906
Provision for credit losses - (benefit) expense	(668)	2,997	(4,028)	1,347
Charge-offs	(332)	(6,350)	(791)	(6,468)
Recoveries	958	132	6,077	222
Ending balance	34,448	28,014	34,448	28,014
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	133,566	130,238	133,020	127,426
Provision for credit losses - (benefit) expense	26,721	14,072	42,901	29,799
Charge-offs	(25,591)	(16,462)	(53,955)	(33,260)
Recoveries	3,613	3,451	16,343	7,281
Ending balance	$ 138,309	$ 131,299	138,309	131,299
Consumer Portfolio Segment [Member] \| Bulk Sale Of Fully Charged-Off Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Recoveries			$ 9,500
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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+ References

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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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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