Finance Receivables, Credit Quality Information, and Allowance for Credit Losses - Summary of Finance Receivables (Detail) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025	Sep. 30, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 2,209,925	$ 2,140,199	$ 2,053,017
Large Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,742,013	1,593,171	1,512,140
Small Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 467,912	$ 547,028	$ 540,877

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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+ Details