Loans and Allowance for Credit Losses - Summary of Aging of Loans and Loans Held for Sale (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	$ 2,437,449	$ 110,243
Total	93,083	2,444,376
Accruing	0	0
Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	2,344,366	2,334,133
30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	46,892	59,625
60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	17,232	22,877
90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	28,959	27,741
Recreation [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,495,059	84,563
Total	65,694	1,492,540
Accruing	0	0
Recreation [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,429,365	1,407,977
Recreation [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	43,128	54,169
Recreation [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	15,301	20,376
Recreation [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	7,265	10,018
Home Improvement [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	806,958	9,225
Total	6,923	831,077
Accruing	0	0
Home Improvement [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	800,035	821,852
Home Improvement [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	3,700	5,407
Home Improvement [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,931	2,432
Home Improvement [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,292	1,386
Commercial Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	121,583	16,337
Total	20,402	111,464
Accruing	0	0
Commercial Loans [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	101,181	95,127
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	0
Commercial Loans [Member] \| 90+ [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	20,402	16,337
Taxi Medallion [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,564	118
Total	64	1,909
Accruing	0	0
Taxi Medallion [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	1,500	1,791
Taxi Medallion [Member] \| 30-59 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	64	49
Taxi Medallion [Member] \| 60-89 [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	0	69
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	12,285	0
Total	0	7,386
Accruing	0	0
Strategic Partnership [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Past Due	12,285	7,386
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

Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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