Amount of increase (decrease) in allowance for loan and lease losses write-offs, net.

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

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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.

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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.

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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.

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

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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ALLOWANCE FOR CREDIT LOSSES FOR LOANS AND FINANCE LEASES - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Jun. 30, 2024	Dec. 31, 2023	Jun. 30, 2023	Dec. 31, 2022
Financing Receivable Allowance For Credit Losses [Line Items]
Increase (decrease) in ACL			$ (14,800)
Provision for credit losses - (benefit) expense	$ 16,470	$ 10,643	41,317	$ 47,669
Net charge-offs	24,000	14,100	56,200	46,600
Increase (decrease) in net charge-offs	9,900		9,500
Recoveries	5,039	6,173	28,634	15,626
Off-Balance Sheet, Credit Loss, Liability, Credit Loss Expense (Reversal)	(1,041)	(128)	(1,177)	488
Off-Balance Sheet, Credit Loss, Liability	3,461	4,761	3,461	4,761	$ 4,502	$ 4,638	$ 4,889	$ 4,273
Charge-offs	29,045	20,259	84,798	62,260
Net disbursements on loans held for investment			365,298	485,198
Allowance for credit losses	246,996	263,615	246,996	263,615	254,532	261,843	267,058	260,464
Residential Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Increase (decrease) in ACL			(16,700)
Provision for credit losses - (benefit) expense	(5,476)	(3,349)	(16,533)	(6,776)
Recoveries	497	534	1,215	1,788
Charge-offs	421	499	1,428	2,628
Allowance for credit losses	40,651	57,200	40,651	57,200	46,051	57,397	60,514	62,760
Residential Portfolio Segment [Member] \| U S [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Charge-offs			0
Commercial Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Increase (decrease) in ACL			(8,800)
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Provision for credit losses - (benefit) expense	(1,659)	(642)	(1,642)	1,420
Recoveries	11	1,463	35	1,935
Charge-offs	0	4	0	42
Allowance for credit losses	3,998	5,621	3,998	5,621	5,646	5,605	4,804	2,308
Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Provision for credit losses - (benefit) expense	1,138	1,931	(2,890)	3,278
Increase (decrease) in net charge-offs	6,200
Recoveries	210	161	6,287	383
Charge-offs	1,350	9	2,141	6,477
Allowance for credit losses	34,446	30,097	34,446	30,097	34,448	33,190	28,014	32,906
Commercial Portfolio Segment [Member] \| U S [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Charge-offs			0
Commercial Portfolio Segment [Member] \| U S [Member] \| Commercial And Industrial Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Charge-offs			307
Commercial Portfolio Segment [Member] \| Puerto Rico [Member] \| Construction Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Recoveries		1,400
Commercial Portfolio Segment [Member] \| Puerto Rico [Member] \| Commercial And Industrial Sector [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Recoveries			5,000
Charge-offs	1,200		1,200
Consumer Portfolio Segment [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Increase (decrease) in ACL			10,700
Provision for credit losses - (benefit) expense	28,381	14,047	71,282	43,846
Recoveries	4,280	3,940	20,623	11,221
Charge-offs	27,274	19,746	81,229	53,006
Allowance for credit losses	$ 143,696	$ 129,540	143,696	$ 129,540	$ 138,309	$ 133,020	$ 131,299	$ 127,426
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Charge-offs			24,273
Consumer Portfolio Segment [Member] \| Bulk Sale Of Nonaccrual Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Recoveries			10,000
Consumer Portfolio Segment [Member] \| U S [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Charge-offs			75
Consumer Portfolio Segment [Member] \| U S [Member] \| Automobile Loan [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Charge-offs			$ 75