Loans and Allowance for Credit Losses - Summary of Aging of Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	$ 69,714	$ 81,013
Total	2,340,968	2,176,412
Accruing	0	0
Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	2,271,254	2,095,399
30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	38,804	44,419
60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	15,271	19,757
90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	15,639	16,837
Recreation [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	54,310	64,416
Total	1,448,509	1,292,591
Accruing	0	0
Recreation [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,394,199	1,228,175
Recreation [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	35,094	40,282
Recreation [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	13,278	15,039
Recreation [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	5,938	9,095
Home Improvement [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	6,935	8,000
Total	777,266	764,069
Accruing	0	0
Home Improvement [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	770,331	756,069
Home Improvement [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	3,637	3,936
Home Improvement [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,993	2,562
Home Improvement [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,305	1,502
Commercial Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	8,396	8,396
Total	110,412	115,536
Accruing	0	0
Commercial Loans [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	102,016	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	73	201
Total	3,482	3,663
Accruing	0	0
Taxi Medallion [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	3,409	3,462
Taxi Medallion [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	73	201
Taxi Medallion [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	0	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	1,299	553
Accruing	0	0
Strategic Partnership [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,299	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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