Loans and Allowance for Credit Losses - Summary of Attributes of Nonperforming Loan Portfolio (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	$ 20,648		$ 20,648		$ 32,550
Unpaid principal balance, With related allowance	21,487		21,487		33,754
Related Allowance, With related allowance	3,107		3,107		10,806
Average Investment Recorded, With related allowance	14,997	$ 37,099	17,189	$ 37,174
Interest Income Recognized, With related allowance	9	114	12	303
Recreation [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	6,506		6,506		9,666
Unpaid principal balance, With related allowance	6,506		6,506		9,666
Related Allowance, With related allowance	276		276		343
Average Investment Recorded, With related allowance	6,361	6,903	6,300	6,895
Interest Income Recognized, With related allowance	7	114	10	303
Home Improvement [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	980		980		579
Unpaid principal balance, With related allowance	980		980		579
Related Allowance, With related allowance	23		23		10
Average Investment Recorded, With related allowance	980	491	865	459
Interest Income Recognized, With related allowance	2	0	2	0
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	9,235		9,235		8,734
Unpaid principal balance, With related allowance	9,344		9,344		8,823
Related Allowance, With related allowance	1,121		1,121		963
Average Investment Recorded, With related allowance	3,085	13,577	5,229	13,494
Interest Income Recognized, With related allowance	0	0	0	0
Medallion [Member]
Financing Receivable, Recorded Investment [Line Items]
Recorded Investment, With related allowance	3,927		3,927		13,571
Unpaid principal balance, With related allowance	4,657		4,657		14,686
Related Allowance, With related allowance	1,687		1,687		$ 9,490
Average Investment Recorded, With related allowance	4,571	16,128	4,795	16,326
Interest Income Recognized, With related allowance	$ 0	$ 0	$ 0	$ 0

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

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- Definition

Impaired Financing Receivables With Related Allowance Related Allowance

+ 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
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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- Definition

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+ References

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- Definition

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- Definition

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