Summary of Significant Accounting Policies - Summary of Finalized Adoption Related to Allowance for Credit Losses on Loans (Detail) - USD ($) $ in Thousands	Jan. 01, 2023	Dec. 31, 2022
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss		$ 63,845
Recreation [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss		41,966
Home Improvement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss		11,340
Commercial [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss		1,049
Medallion [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss		9,490
Strategic Partnership [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss		$ 0
December 31, 2022 Pre-Topic 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	$ 77,557
December 31, 2022 Pre-Topic 326 Adoption | Recreation [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	52,003
December 31, 2022 Pre-Topic 326 Adoption | Home Improvement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	12,858
December 31, 2022 Pre-Topic 326 Adoption | Commercial [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	3,206
December 31, 2022 Pre-Topic 326 Adoption | Medallion [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	9,490
December 31, 2022 Pre-Topic 326 Adoption | Strategic Partnership [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	0
Effect of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	13,712
Effect of ASC 326 Adoption | Recreation [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	10,037
Effect of ASC 326 Adoption | Home Improvement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	1,518
Effect of ASC 326 Adoption | Commercial [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	2,157
Effect of ASC 326 Adoption | Medallion [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	0
Effect of ASC 326 Adoption | Strategic Partnership [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans, allowance for credit loss	$ 0