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LOANS AND LEASES RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES ON LOANS AND LEASES - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Financing Receivable, Troubled Debt Restructuring [Line Items]
Accrued interest	$ 89,200		$ 89,900
Loans receivable, excluding accrued interest	$ 17,792,583		16,600,758
Loans held for sale, average life from purchase to sale	30 days
Allowance for credit loss, excluding accrued interest	$ 164,106	$ 160,962	155,656	$ 147,418	$ 141,076	$ 136,775
Allowance for credit loss, period increase	8,400
Number of commitments to lend additional funds (commitment)	0
Total consumer loans receivable	16,213,020		15,036,672
Asset Pledged as Collateral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total consumer loans receivable	10,500,000		9,400,000
Consumer Installment Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total non-accrual loans	1,200
Commercial Real Estate \| Other commercial and industrial \| Collateral Dependent Loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans receivable, excluding accrued interest	$ 48,800		$ 34,200