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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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NATURE OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Loans held for investment (Detail) - USD ($) $ in Thousands		12 Months Ended
	Sep. 01, 2020	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Threshold Period Past Due Of Financing Receivables To Be Considered Nonperforming		90 days
Troubled Debt Restructurings Sustained Performance Period		6 months
Loans held for investment		$ 11,552,825	$ 11,060,658
Minimum balance of uncollectible loans to be written down		500
BSPR
Financing Receivable, Past Due [Line Items]
Fair value of PCD loans	$ 752,800
ACL for PCD loans	$ 28,700
Residential Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		$ 2,847,290	2,978,895
Loans Foreclosure Delinquency Threshold		120 days
Financing Receivable, Threshold Period Past Due, Writeoff		180 days
Residential Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		$ 42,772	55,127
Residential Portfolio Segment [Member] \| PCD loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		$ 101,700
Residential Portfolio Segment [Member] \| Puerto Rico Housing Finance Authority [Member]
Financing Receivable, Past Due [Line Items]
Period Of Guaranteed Residential Mortgage Loans That Are No Longer Accruing Interest		90 days
Residential Portfolio Segment [Member] \| FHA/VA government-guaranteed loans [Member]
Financing Receivable, Past Due [Line Items]
Period Of Guaranteed Residential Mortgage Loans That Are No Longer Accruing Interest		15 months
Loans held for investment		$ 118,158	125,392
Residential Portfolio Segment [Member] \| FHA/VA government-guaranteed loans [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		$ 0	0
Residential Portfolio Segment [Member] \| FHA/VA government-guaranteed loans [Member] \| Puerto Rico Housing Finance Authority [Member]
Financing Receivable, Past Due [Line Items]
Past due 90 days and still accruing		90 days
Commercial Portfolio Segment [Member] \| PCD loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		$ 1,900
Commercial Portfolio Segment [Member] \| Mortgage Receivable [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		2,358,851	2,167,469
Commercial Portfolio Segment [Member] \| Commercial And Industrial Sector [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		2,886,263	2,887,251
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		132,953	138,999
Consumer Portfolio Segment [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		3,327,468	2,888,044
Consumer Portfolio Segment [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		14,806	10,454
Consumer Portfolio Segment [Member] \| Auto loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		1,798,071	1,571,540
Consumer Portfolio Segment [Member] \| Auto loans [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		10,672	6,684
Consumer Portfolio Segment [Member] \| Personal Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		$ 353,246	316,182
Financing Receivable, Threshold Period Past Due, Writeoff		120 days
Consumer Portfolio Segment [Member] \| Personal Loans [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		$ 1,248	1,208
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		146,190	135,091
Consumer Portfolio Segment [Member] \| Other Loans [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		1,241	1,696
Consumer Portfolio Segment [Member] \| Finance Leases [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		718,230	575,005
Consumer Portfolio Segment [Member] \| Finance Leases [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		1,645	866
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		$ 311,731	290,226
Financing Receivable, Threshold Period Past Due, Writeoff		180 days
Consumer Portfolio Segment [Member] \| Credit Card Receivables [Member] \| Nonperforming Financial Instruments [Member]
Financing Receivable, Past Due [Line Items]
Loans held for investment		$ 0	$ 0