Income Taxes - Summary of Components of Deferred and Other Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands		Sep. 30, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Goodwill and other intangibles		$ 43,125	$ 43,397
Provision for credit losses		(11,491)	(9,945)
Net operating loss carryforwards	[1]	(3,804)	(3,730)
Accrued expenses, compensation, and other assets		(6,038)	(3,819)
Unrealized gains on other investments		(2,094)	(1,445)
Total deferred tax liability		19,698	24,458
Valuation allowance		3,433	2,295
Deferred tax liability, net		$ 23,131	$ 26,753

[1] As of September 30, 2023, the Company had an estimated $11.1 million of net operating loss carryforwards, $1.7 million of which expires at various dates between December 31, 2026 and December 31, 2035, which had a net carrying value of $0.4 million as of September 30, 2023.