Loans - Summary of Loan Balances (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Loans and Leases Receivable Disclosure [Line Items]
Total	$ 5,851,975	$ 4,916,624
Total principal balance of loans owed, net of charge-offs	5,900,663	4,946,653
Unamortized net deferred loan fees	(13,780)	(13,922)
Discounts to principal balance of loans owed, net of charge-offs	(34,908)	(16,107)
Allowance for credit losses	(96,049)	(85,376)	$ (85,941)	$ (91,847)
Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total	3,832,974	3,306,054
Allowance for credit losses	(54,992)	(51,140)	(50,403)	(53,693)
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total	1,136,712	1,071,551
Allowance for credit losses	(23,679)	(23,474)	(24,604)	(25,148)
Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Total	500,882	259,355
Allowance for credit losses	(9,042)	(3,862)	(4,464)	(4,252)
Construction
Loans and Leases Receivable Disclosure [Line Items]
Total	303,960	222,281
Allowance for credit losses	(7,437)	(5,667)	(5,476)	(7,540)
Agriculture production
Loans and Leases Receivable Disclosure [Line Items]
Total	69,339	50,811
Allowance for credit losses	(883)	(1,215)	(988)	(1,209)
Leases
Loans and Leases Receivable Disclosure [Line Items]
Total	8,108	6,572
Allowance for credit losses	(16)	(18)	(6)	(5)
CRE non-owner occupied | Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total	1,891,022	1,603,141
Allowance for credit losses	(28,055)	(25,739)	(26,434)	(29,380)
CRE owner occupied | Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total	851,434	706,307
Allowance for credit losses	(12,071)	(10,691)	(9,874)	(10,861)
Multifamily | Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total	839,918	823,500
Allowance for credit losses	(11,987)	(12,395)	(12,371)	(11,472)
Farmland | Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Total	250,600	173,106
Allowance for credit losses	(2,879)	(2,315)	(1,724)	(1,980)
SFR 1-4 1st DT liens | Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total	711,389	666,960
SFR HELOCs and junior liens | Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total	362,501	337,513
Allowance for credit losses	(10,843)	(10,510)	(11,079)	(11,771)
Other | Consumer
Loans and Leases Receivable Disclosure [Line Items]
Total	62,822	67,078
Allowance for credit losses	$ (2,167)	$ (2,241)	$ (2,860)	$ (3,260)