Subordinated Debt - Summary of Subordinated Debt (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Subordinated Borrowings [Abstract]
Subordinated debt	$ 25,000	$ 10,000
Unamortized issuance costs	(511)	(200)
Subordinated debt, net	$ 24,489	$ 9,800

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant