Loans and Lease Finance Receivables and Allowance for Credit Losses - Schedule of Recorded Investment in, and Aging of, Past Due and Nonaccrual Loans, Including PCI Loans by Class of Loans (Parenthetical) (Detail) - USD ($)
$ in Thousands

Sep. 30, 2026

Dec. 31, 2025

Accounts, Notes, Loans and Financing Receivable [Line Items]

Nonaccruing loans, current

$ 4,500

18,725

^[1],[2],[3]

$ 4,685

^[4],[5]

Accounts, Notes, Loans and Financing Receivable [Line Items]

2,652

^[1],[2],[3]

21

^[4],[5]

Nonaccrual loans

35,000

3,000

30-59 Days Past Due [Member]

Accounts, Notes, Loans and Financing Receivable [Line Items]

30,000

60-89 Days Past Due [Member]

Accounts, Notes, Loans and Financing Receivable [Line Items]

32,000

90+ Days Past Due [Member]

Accounts, Notes, Loans and Financing Receivable [Line Items]

$ 14,200

$ 4,700

[1]	As of September 30, 2026, $4.5 million of nonaccruing loans were current, $30,000 were 30-59 days past due, $32,000 were 60-89 days past due, and $14.2 million were 90+ days past due.
[2]	Excludes $35,000 of guaranteed portion of nonaccrual SBA loans that are in process of collection.
[3]	Speculative construction loans are generally for properties where there is no identified buyer or renter.
[4]	As of December 31, 2025, $4.7 million were 90+ days past due.
[5]	Excludes $3,000 of guaranteed portion of nonaccrual SBA loans that are in process of collection.