Loans Held for Investment (LHFI) and Allowance for Loan Losses, LHFI - Additional Information (Details 2)	3 Months Ended
	Mar. 31, 2022 USD ($) KeyRatio	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Financing Receivable Recorded Investment [Line Items]
Number of days used as baseline in evaluating collateral documentation exceptions for loan policy	90 days
Number of key quality ratios | KeyRatio	6
Exposure for commercial non accrual loans to be reviewed on individual basis	$ 500,000
Exposure for commercial accrual loans deemed to be reviewed on individual basis	500,000
LHFS past due 90 days or more	$ 62,100,000		$ 69,900,000
Percentage of outstanding principal to be repurchased under GNMA optional repurchase program	100.00%
Financing Receivable [Abstract]
PCL	$ (860,000)	$ (10,501,000)
Commercial and Industrial Loans [Member]
Financing Receivable [Abstract]
PCL		4,100
Allowance for Credit Losses, ACL [Member]
Financing Receivable [Abstract]
PCL	(860,000)	(10,501,000)
Allowance for Credit Losses, ACL [Member] | Commercial and Industrial Loans [Member]
Financing Receivable [Abstract]
PCL	(3,803,000)	4,051,000
Allowance for Credit Losses, ACL [Member] | State and Other Political Subdivision Loans [Member]
Financing Receivable [Abstract]
PCL	(337,000)	(175,000)
Allowance for Credit Losses, ACL [Member] | Other Commercial Loans [Member]
Financing Receivable [Abstract]
PCL	(863,000)	$ 1,243,000
Minimum [Member]
Financing Receivable [Abstract]
Credit amount used as baseline in evaluating loan policy	$ 100,000