Loans and Allowance for Loan Losses - Summary of Activities of the Loan Collateral in Process of Foreclosure Related to Recreation and Medallion Loans (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020		Mar. 31, 2019
Loans and Leases Receivable Disclosure [Line Items]
Loans collateral in process of foreclosure - beginning balance	$ 52,711	[1]	$ 49,495
Transfer from loans, net	6,938		9,096
Sales	(2,299)		(2,453)
Cash payments received	(1,708)		(2,573)
Collateral valuation adjustments	(8,825)		(3,757)
Loans collateral in process of foreclosure - ending balance	46,817	[1]	49,808
Recreation [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collateral in process of foreclosure - beginning balance	1,476		1,503
Transfer from loans, net	4,779		3,391
Sales	(1,999)		(2,076)
Collateral valuation adjustments	(2,539)		(1,638)
Loans collateral in process of foreclosure - ending balance	1,717		1,180
Medallion [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans collateral in process of foreclosure - beginning balance	51,235		47,992
Transfer from loans, net	2,159		5,705
Sales	(300)		(377)
Cash payments received	(1,708)		(2,573)
Collateral valuation adjustments	(6,286)		(2,119)
Loans collateral in process of foreclosure - ending balance	$ 45,100		$ 48,628

[1] Includes financed sales of this collateral to third parties that are reported separately from the loan portfolio, and that are conducted by the Bank of $9,157 as of March 31, 2020 and $8,163 as of December 31, 2019.