Goodwill and Other Intangible Assets - Components of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 41,841	$ 36,746
Accumulated amortization	29,993	27,880
Net carrying amount	11,848	8,866
Core Deposits [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	6,788	6,788
Accumulated amortization	5,425	4,787
Net carrying amount	1,363	2,001
Customer Related Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	8,493	7,604
Accumulated amortization	5,886	7,147
Net carrying amount	2,607	457
Servicing Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	26,560	22,354
Accumulated amortization	18,682	15,946
Net carrying amount	7,878	6,408
Valuation allowance included in accumulated amortization	$ 13	$ 87	$ 0	$ 0