Loans and Allowance for Loan Losses - Summary of Activity in Allowance for Loan Losses (Detail) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - beginning balance		$ 50,686	$ 57,809	$ 50,166	$ 57,548
Total charge-offs		6,182	(16,249)	(13,968)	(23,097)
Total recoveries		6,889	6,068	11,955	10,159
Net recoveries (charge-offs)	[1]	707	(10,181)	(2,013)	(12,938)
Provision (benefit) for loan losses		7,759	(682)	10,999	2,336
Allowance for loan losses - ending balance	[1],[2]	59,152	46,946	59,152	46,946
Recreation [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - beginning balance				32,435
Total charge-offs		5,074	(2,672)	(10,141)	(7,725)
Total recoveries		3,615	3,588	7,125	6,057
Allowance for loan losses - ending balance		37,772		37,772
Home Improvement [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - beginning balance				7,356
Total charge-offs		1,108	(786)	(2,168)	(1,467)
Total recoveries		585	558	1,144	990
Allowance for loan losses - ending balance		9,234		9,234
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - beginning balance				1,141
Total charge-offs		0	0	(1,584)	0
Total recoveries		13	0	47	0
Allowance for loan losses - ending balance		2,720		2,720
Medallion [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses - beginning balance				9,234
Total charge-offs		0	(12,791)	(75)	(13,905)
Total recoveries		2,676	$ 1,922	3,639	$ 3,112
Allowance for loan losses - ending balance		$ 9,426		$ 9,426

[1] As of June 30, 2022, cumulative net charge-offs of loans and loan collateral in process of foreclosure in the medallion loan portfolio were $252.1 million, some of which may represent collection opportunities for the Company.

[2] As of June 30, 2022 and June 30, 2021, there were no allowance for loan losses and net charge-offs related to the strategic partnership loans.