Loans and Allowance for Credit Losses - Summary of Attributes of Nonperforming Loan Portfolio (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	$ 21,881		$ 25,974
Unpaid principal balance, With related allowance	22,697		26,796
Related Allowance, With related allowance	4,156		3,890
Average Investment Recorded, With related allowance	22,581	$ 16,842
Interest Income (Expense) Recognized, With related allowance	17	14
Recreation [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	6,872		9,655
Unpaid principal balance, With related allowance	6,872		9,655
Related Allowance, With related allowance	302		416
Average Investment Recorded, With related allowance	6,721	4,656
Interest Income (Expense) Recognized, With related allowance	16	13
Home Improvement [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	1,359		1,493
Unpaid principal balance, With related allowance	1,359		1,493
Related Allowance, With related allowance	32		41
Average Investment Recorded, With related allowance	1,363	441
Interest Income (Expense) Recognized, With related allowance	1	1
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	10,090		11,163
Unpaid principal balance, With related allowance	10,243		11,301
Related Allowance, With related allowance	2,320		1,897
Average Investment Recorded, With related allowance	10,243	5,652
Interest Income (Expense) Recognized, With related allowance	0	0
Taxi Medallion [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	3,560		3,663
Unpaid principal balance, With related allowance	4,223		4,347
Related Allowance, With related allowance	1,502		$ 1,536
Average Investment Recorded, With related allowance	4,254	6,093
Interest Income (Expense) Recognized, With related allowance	$ 0	$ 0

Impaired financing receivable with related allowance interest income and adjusted interest expense accrual method.

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- Definition

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+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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-Name Accounting Standards Codification
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- Definition

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