Loans and Allowance for Credit Losses - Summary of Activity in Allowance for Loan Losses (Parenthetical) (Detail) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2024		Mar. 31, 2023	Dec. 31, 2023	[1]	Dec. 31, 2022
Financing Receivable, Allowance for Credit Losses [Line Items]
Cumulative charges of loans and loan collateral process of foreclosure		$ 10,198	[1]	$ 20,467	$ 11,772		$ 21,819
Net charge-offs	[2]	17,609		11,315
Strategic Partnership [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Net charge-offs		0		$ 0
Medallion Bank [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Cumulative charges of loans and loan collateral process of foreclosure		173,700
New York Taxi Medallion [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Cumulative charges of loans and loan collateral process of foreclosure		$ 105,500

[1] Includes financed sales of this collateral to third parties that are reported separately from the loan portfolio, of $5.8 million as of March 31, 2024 and $6.2 million as of December 31, 2023.

[2] As of March 31, 2024, cumulative net charge-offs of loans and loan collateral in process of foreclosure in the taxi medallion loan portfolio were $173.7 million, including $105.5 million related to loans secured by New York City taxi medallions, some of which may represent collection opportunities for the Company.