Description of Business and Summary of Significant Accounting Policies - Narrative (Details)			12 Months Ended
	Jun. 01, 2020 USD ($)	May 29, 2020 USD ($)	Dec. 31, 2021 USD ($) branch	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Property, Plant and Equipment [Line Items]
Percentage of capital stock of the Bank held			100.00%
Number of depository branches | branch			61
Cash reserves required by the Federal Reserve			$ 0
ACL recorded related to PCD loans				$ 21,242,000
Loans held for investment			197,752,000	268,018,000	$ 35,698,000	$ 36,072,000
Off-balance sheet, credit loss, liability			27,300,000	31,100,000
Valuation allowance			$ 0	0
Cumulative effect of the change in accounting principle
Property, Plant and Equipment [Line Items]
Loans held for investment					55,686,000
Off-balance sheet, credit loss, liability					$ 8,300,000
Core Deposits | Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life (in years)			6 years
Core Deposits | Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life (in years)			11 years
Opus
Property, Plant and Equipment [Line Items]
Total merger consideration	$ 749,605,000	$ 749,605,000
Aggregate fair value of PCD loans acquired	841,234,000
ACL recorded related to PCD loans	$ 21,200,000			$ 21,200,000
Premises
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)			20 years
Furniture, fixtures, and equipment
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)			7 years
Computer and telecommunication
Property, Plant and Equipment [Line Items]
Estimated useful life (in years)			3 years