Disclosures About Fair Value of Assets and Liabilities - Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements Other Than Goodwill (Details) - Significant Unobservable Inputs (Level 3) $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 31, 2021	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
State and municipal securities | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value		$ 5,565	$ 2,444
State and municipal securities | Discounted cash flow | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Maturity/Call date	1 month	1 month
US Muni BQ curve	BBB-	BBB-
State and municipal securities | Discounted cash flow | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Maturity/Call date	15 years	15 years
US Muni BQ curve	A-	A-
State and municipal securities | Discounted cash flow | Discount rate | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount rate		0.0075	0.0150
State and municipal securities | Discounted cash flow | Discount rate | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount rate		0.04	0.04
State and municipal securities | Discounted cash flow | Weighted-average coupon | Weighted-average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount rate		0.04	0.04
Corporate obligations and U.S. Government-sponsored mortgage-backed securities | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value		$ 35	$ 35
Corporate obligations and U.S. Government-sponsored mortgage-backed securities | Discounted cash flow | Weighted-average coupon | Weighted-average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount rate		0	0
Corporate obligations and U.S. Government-sponsored mortgage-backed securities | Discounted cash flow | Risk free rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Risk free rate	3 month LIBOR	3 month LIBOR
Corporate obligations and U.S. Government-sponsored mortgage-backed securities | Discounted cash flow | plus premium for illiquidity
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount rate		0.02	0.02
Collateral dependent loans | Collateral based measurements
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value		$ 31,408	$ 37,250
Collateral dependent loans | Collateral based measurements | Discount to reflect current market conditions and ultimate collectability | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount to reflect current market conditions and ultimate collectability		0	0
Collateral dependent loans | Collateral based measurements | Discount to reflect current market conditions and ultimate collectability | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount to reflect current market conditions and ultimate collectability		0.10	0.10
Collateral dependent loans | Collateral based measurements | Discount to reflect current market conditions and ultimate collectability | Weighted-average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Discount to reflect current market conditions and ultimate collectability		0.05	0.06
Other real estate owned | Appraisals
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair Value		$ 96	$ 544
Other real estate owned | Appraisals | Discount to reflect current market conditions | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other real estate owned		0	0
Other real estate owned | Appraisals | Discount to reflect current market conditions | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other real estate owned		0.72	0.30
Other real estate owned | Appraisals | Discount to reflect current market conditions | Weighted-average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Other real estate owned		0.44	0.26