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LOANS AND LEASES RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES ON LOANS AND LEASES - Additional Information (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items]
Accrued interest	$ 88,900		$ 88,200
Loans receivable, excluding accrued interest	$ 16,120,441		14,311,987
Loans held for sale, average life from purchase to sale	30 days
Allowance for credit loss, excluding accrued interest	$ 151,809	$ 147,418	136,775	$ 133,158	$ 132,436	$ 135,311
Allowance for credit loss, period increase	15,000
Number of commitments to lend additional funds (commitment)	0
Total consumer loans receivable	14,668,170		13,104,883
Asset Pledged as Collateral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total consumer loans receivable	8,600,000		8,000,000
Consumer Installment Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total nonaccrual loans	1,900
Commercial Real Estate \| Other commercial and industrial \| Collateral Dependent Loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans receivable, excluding accrued interest	$ 19,900		$ 31,900