Loans and Allowance for Loan Losses - Schedule of Activity of Gross Loans (Detail) - USD ($)		3 Months Ended
		Mar. 31, 2022	Mar. 31, 2021
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance	[1]	$ 1,461,622,000
Charge-offs	[2]	2,720,000	$ 2,758,000
Transfer to loan collateral in process of foreclosure, net		(3,040,000)	(3,802,000)
Amortization of origination costs		(2,119,000)	(1,656,000)
Paid-in-kind interest		172,000	325,000
Gross loans, ending balance	[3]	1,540,642,000
Recreation [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance	[1]	931,859,000
Transfer to loan collateral in process of foreclosure, net		(2,911,000)	(3,053,000)
Gross loans, ending balance	[3]	973,172,000
Home Improvement [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance	[1]	438,931,000
Gross loans, ending balance	[3]	475,527,000
Medallion [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance	[1]	14,046,000
Transfer to loan collateral in process of foreclosure, net		(129,000)	(749,000)
Gross loans, ending balance	[3]	13,850,000
Strategic Partnership [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance	[1]	90,000
Charge-offs		0	0
Gross loans, ending balance	[3]	226,000
Bank Holding Company Accounting [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		1,488,924,000	1,229,838,000
Loan originations		213,727,000	148,009,000
Principal payments, sales, maturities, and recoveries		124,055,000	109,106,000
Charge-offs		7,786,000	6,848,000
Transfer to loan collateral in process of foreclosure, net		3,040,000	3,749,000
Amortization of origination costs		(2,119,000)	(1,656,000)
Amortization of loan premium		150,000	187,000
FASB origination costs		3,768,000	2,589,000
Paid-in-kind interest		172,000	325,000
Gross loans, ending balance		1,569,441,000	1,259,215,000
Bank Holding Company Accounting [Member] | Recreation [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		961,320,000	792,686,000
Loan originations		114,406,000	93,850,000
Principal payments, sales, maturities, and recoveries		65,116,000	55,958,000
Charge-offs		5,067,000	5,053,000
Transfer to loan collateral in process of foreclosure, net		2,911,000	3,053,000
Amortization of origination costs		(2,439,000)	(2,162,000)
Amortization of loan premium		60,000	41,000
FASB origination costs		3,958,000	2,663,000
Paid-in-kind interest
Gross loans, ending balance		1,004,091,000	822,932,000
Bank Holding Company Accounting [Member] | Home Improvement [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		436,772,000	334,033,000
Loan originations		89,820,000	48,059,000
Principal payments, sales, maturities, and recoveries		52,164,000	39,637,000
Charge-offs		1,060,000	681,000
Transfer to loan collateral in process of foreclosure, net
Amortization of origination costs		320,000	497,000
Amortization of loan premium		90,000	76,000
FASB origination costs		(190,000)	(74,000)
Paid-in-kind interest
Gross loans, ending balance		473,408,000	342,121,000
Bank Holding Company Accounting [Member] | Commercial [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		76,696,000	65,327,000
Loan originations		4,400,000	4,156,000
Principal payments, sales, maturities, and recoveries		1,817,000	10,965,000
Charge-offs		1,584,000
Transfer to loan collateral in process of foreclosure, net
Amortization of origination costs			11,000
Amortization of loan premium
FASB origination costs
Paid-in-kind interest		172,000	325,000
Gross loans, ending balance		77,867,000	58,854,000
Bank Holding Company Accounting [Member] | Medallion [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		14,046,000	37,768,000
Loan originations		92,000
Principal payments, sales, maturities, and recoveries		85,000	636,000
Charge-offs		75,000	1,114,000
Transfer to loan collateral in process of foreclosure, net		129,000	696,000
Amortization of origination costs			(2,000)
Amortization of loan premium			70,000
FASB origination costs
Paid-in-kind interest
Gross loans, ending balance		13,849,000	35,250,000
Bank Holding Company Accounting [Member] | Strategic Partnership [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		90,000	24,000
Loan originations		5,009,000	1,944,000
Principal payments, sales, maturities, and recoveries		4,873,000	1,910,000
Charge-offs
Transfer to loan collateral in process of foreclosure, net
Amortization of origination costs
Amortization of loan premium
FASB origination costs
Paid-in-kind interest
Gross loans, ending balance		$ 226,000	$ 58,000

[1] Excludes loan premiums of $0.5 million and $26.8 million of capitalized loan origination costs.

[2] As of March 31, 2022, cumulative net charge-offs of loans and loan collateral in process of foreclosure in the medallion loan portfolio were $257.0 million, some of which may represent collection opportunities for the Company.

[3] Excludes loan premiums of $0.4 million and $28.4 million of capitalized loan origination costs.  December 31, 2021   Days Past Due                       Recorded
Investment
90 Days and   (Dollars in thousands)   30-59     60-89     90 +     Total     Current     Total (1)     Accruing   Recreation   $ 20,037     $ 6,569     $ 3,818     $ 30,424     $ 901,435     $ 931,859     $ —   Home improvement     1,517       479       132       2,128       436,803       438,931       —   Commercial     1,795       —       74       1,869       74,827       76,696       —   Medallion     215       7,125       —       7,340       6,706       14,046       —   Strategic partnership     —       —       —       —       90       90       —   Total   $ 23,564     $ 14,173     $ 4,024     $ 41,761     $ 1,419,861     $ 1,461,622     $ —