Loans and Allowance for Credit Losses - Summary of Aging of Loans (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	$ 70,517	$ 81,013
Total	2,188,640	2,176,412
Accruing	0	0
Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	2,118,123	2,095,399
30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	40,700	44,419
60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	13,685	19,757
90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	16,132	16,837
Recreation [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	55,484	64,416
Total	1,320,794	1,292,591
Accruing	0	0
Recreation [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,265,310	1,228,175
Recreation [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	37,205	40,282
Recreation [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	11,905	15,039
Recreation [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	6,374	9,095
Home Improvement [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	6,537	8,000
Total	755,831	764,069
Accruing	0	0
Home Improvement [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	749,294	756,069
Home Improvement [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	3,495	3,936
Home Improvement [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,680	2,562
Home Improvement [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,362	1,502
Commercial Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	8,396	8,396
Total	107,586	115,536
Accruing	0	0
Commercial Loans [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	99,190	107,140
Commercial Loans [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	0	0
Commercial Loans [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	0	2,156
Commercial Loans [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	8,396	6,240
Taxi Medallion [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	100	201
Total	3,560	3,663
Accruing	0	0
Taxi Medallion [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	3,460	3,462
Taxi Medallion [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	0	201
Taxi Medallion [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	100	0
Taxi Medallion [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	0	0
Strategic Partnership [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	0	0
Total	869	553
Accruing	0	0
Strategic Partnership [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	869	553
Strategic Partnership [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	0	0
Strategic Partnership [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	0	0
Strategic Partnership [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	$ 0	$ 0

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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