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

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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LOANS AND LEASES RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES ON LOANS AND LEASES - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items]
Accrued interest	$ 85,900	$ 85,900		$ 88,200
Loans receivable, excluding accrued interest	15,232,019	$ 15,232,019		14,311,987
Loans held for sale, average life from purchase to sale		30 days
Allowance for credit loss, excluding accrued interest	147,418	$ 147,418	$ 141,076	136,775	$ 132,436	$ 133,296	$ 135,311
Allowance for credit loss, period increase		10,600
Number of commitments to lend additional funds (commitment)	0	0
Total consumer loans receivable	13,708,767	13,708,767		13,104,883
Asset Pledged as Collateral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total consumer loans receivable	7,900,000	7,900,000		8,000,000
Consumer Installment Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Total nonaccrual loans	2,000	2,000
Commercial and industrial, including specialized lending
Financing Receivable, Troubled Debt Restructuring [Line Items]
Allowance for credit loss, excluding accrued interest	36,262	36,262	$ 30,584	29,379	$ 23,721	$ 23,003	$ 23,503
Total consumer loans receivable	7,570,793	7,570,793		7,002,019
Par value	32,050	32,050
Commercial Real Estate \| Other commercial and industrial \| Collateral Dependent Loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Loans receivable, excluding accrued interest	$ 18,300	$ 18,300		$ 31,900