Borrowings - Schedule of Subordinated Debentures (Detail) - Trust Preferred Securities [Member] - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument Redemption [Line Items]
Subordinated debentures contractual balance	$ 28,352	$ 28,352
Subordinated debentures fair market value adjustments	(5,346)	(5,428)
Total subordinated debentures	23,006	22,924
FCB Capital Trust II [Member]
Debt Instrument Redemption [Line Items]
Subordinated debentures contractual balance	$ 10,310	$ 10,310
Subordinated debentures, Weighted Average Rate	2.24%	2.12%
Subordinated debentures, Weighted Average Term	13 years	13 years 3 months 18 days
FCB Capital Trust III [Member]
Debt Instrument Redemption [Line Items]
Subordinated debentures contractual balance	$ 5,155	$ 5,155
Subordinated debentures, Weighted Average Rate	2.72%	2.08%
Subordinated debentures, Weighted Average Term	15 years 2 months 12 days	15 years 6 months
Community First Statutory Trust I [Member]
Debt Instrument Redemption [Line Items]
Subordinated debentures contractual balance	$ 5,155	$ 5,155
Subordinated debentures, Weighted Average Rate	4.22%	3.47%
Subordinated debentures, Weighted Average Term	10 years 8 months 12 days	11 years
American State Bank Statutory Trust I [Member]
Debt Instrument Redemption [Line Items]
Subordinated debentures contractual balance	$ 7,732	$ 7,732
Subordinated debentures, Weighted Average Rate	2.63%	2.00%
Subordinated debentures, Weighted Average Term	13 years 6 months	13 years 9 months 18 days