Loans and Allowance for Loan Losses - Schedule of Activity of Gross Loans (Detail) - USD ($)		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance	[1]			$ 1,136,694,000
Charge-offs, net	[2]	$ (4,021,000)	$ (11,363,000)	(12,598,000)	$ (24,239,000)
Transfer to loan collateral in process of foreclosure, net		(5,188,000)	(10,354,000)	(12,125,000)	(19,451,000)
Amortization of origination costs				(2,891,000)	(2,389,000)
Paid-in-kind interest				634,000	425,000
Gross loans, ending balance	[3]	1,234,687,000		1,234,687,000
Recreation [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance	[1]			689,810,000
Transfer to loan collateral in process of foreclosure, net		(3,003,000)	(3,491,000)	(7,781,000)	(6,883,000)
Gross loans, ending balance	[3]	761,403,000		761,403,000
Home Improvement [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance	[1]			250,830,000
Gross loans, ending balance	[3]	285,455,000		285,455,000
Medallion [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance	[1]			126,287,000
Transfer to loan collateral in process of foreclosure, net		(2,185,000)	(6,863,000)	(4,344,000)	(12,568,000)
Gross loans, ending balance	[3],[4]	116,345,000		116,345,000
Strategic Partnership [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Charge-offs, net		0	0	0	0
Gross loans, ending balance	[3]	8,000		8,000
Bank Holding Company Accounting [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		1,183,779,000	1,024,200,000	1,160,855,000	1,017,882,000
Loan originations		154,072,000	145,498,000	259,356,000	236,277,000
Principal payments, sales and maturities		(69,917,000)	(60,313,000)	(137,286,000)	(122,616,000)
Charge-offs, net		(4,021,000)	(11,363,000)	(12,598,000)	(24,239,000)
Transfer to loan collateral in process of foreclosure, net		(5,188,000)	(10,354,000)	(12,125,000)	(19,451,000)
Amortization of origination costs		(1,587,000)	(1,238,000)	(2,891,000)	(2,389,000)
Amortization of loan premium		(179,000)	(1,081,000)	(508,000)	(2,173,000)
FASB origination costs		3,294,000	2,938,000	5,157,000	4,759,000
Paid-in-kind interest		341,000	188,000	634,000	425,000
Gross loans, ending balance		1,260,594,000	1,088,475,000	1,260,594,000	1,088,475,000
Bank Holding Company Accounting [Member] | Recreation [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		735,175,000	609,999,000	713,332,000	587,038,000
Loan originations		106,206,000	102,695,000	175,850,000	166,327,000
Principal payments, sales and maturities		(49,457,000)	(40,088,000)	(86,529,000)	(73,140,000)
Charge-offs, net		(3,565,000)	(2,433,000)	(9,946,000)	(7,363,000)
Transfer to loan collateral in process of foreclosure, net		(3,003,000)	(3,491,000)	(7,781,000)	(6,883,000)
Amortization of origination costs		(2,031,000)	(1,582,000)	(3,760,000)	(3,020,000)
Amortization of loan premium		(51,000)	(67,000)	(103,000)	(136,000)
FASB origination costs		3,511,000	3,507,000	5,722,000	5,717,000
Gross loans, ending balance		786,785,000	668,540,000	786,785,000	668,540,000
Bank Holding Company Accounting [Member] | Home Improvement [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		255,899,000	193,275,000	247,324,000	183,155,000
Loan originations		44,713,000	33,533,000	78,178,000	60,180,000
Principal payments, sales and maturities		(18,496,000)	(16,837,000)	(42,720,000)	(33,072,000)
Charge-offs, net		(196,000)	(86,000)	(832,000)	(245,000)
Amortization of origination costs		455,000	347,000	896,000	693,000
Amortization of loan premium		(82,000)	(111,000)	(168,000)	(220,000)
FASB origination costs		(221,000)	(572,000)	(606,000)	(942,000)
Gross loans, ending balance		282,072,000	209,549,000	282,072,000	209,549,000
Bank Holding Company Accounting [Member] | Commercial [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		68,257,000	55,211,000	69,767,000	64,083,000
Loan originations		3,000,000	9,270,000	5,175,000	9,770,000
Principal payments, sales and maturities		(132,000)	(226,000)	(4,112,000)	(9,805,000)
Amortization of origination costs		2,000	1,000	4,000	30,000
FASB origination costs		8,000	(2,000)	8,000	(61,000)
Paid-in-kind interest		341,000	188,000	634,000	425,000
Gross loans, ending balance		71,476,000	64,442,000	71,476,000	64,442,000
Bank Holding Company Accounting [Member] | Medallion [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Gross loans, beginning balance		124,448,000	165,715,000	130,432,000	183,606,000
Principal payments, sales and maturities		(1,687,000)	(3,162,000)	(3,780,000)	(6,599,000)
Charge-offs, net		(260,000)	(8,844,000)	(1,820,000)	(16,631,000)
Transfer to loan collateral in process of foreclosure, net		(2,185,000)	(6,863,000)	(4,344,000)	(12,568,000)
Amortization of origination costs		(13,000)	(4,000)	(31,000)	(92,000)
Amortization of loan premium		(46,000)	(903,000)	(237,000)	(1,817,000)
FASB origination costs		(4,000)	5,000	33,000	45,000
Gross loans, ending balance		120,253,000	$ 145,944,000	120,253,000	$ 145,944,000
Bank Holding Company Accounting [Member] | Strategic Partnership [Member]
Schedule Of Gross Real Estate And Loan Activity [Line Items]
Loan originations		153,000		153,000
Principal payments, sales and maturities		(145,000)		(145,000)
Gross loans, ending balance		$ 8,000		$ 8,000

[1] Excludes loan premiums of $5,758 resulting from purchase price accounting and $18,403 of capitalized loan origination costs.

[2] As of June 30, 2020, cumulative net charge-offs of loans and loan collateral in process of foreclosure in the medallion loan portfolio were $245,058, representing collection opportunities for the Company.

[3] Excludes loan premiums of $5,251 resulting from purchase price accounting and $20,656 of capitalized loan origination costs.

[4] Included in the current medallion loan aging bucket were $80,403 of loans that had been granted deferral status under the CARES Act, some or all of which may have become delinquent had they not been granted the deferral status.