Fair Value Disclosures - Quantitative information about Level 3 fair value measurements for assets - Non recurring basis (Details) - Non - recurring - Appraisal of collateral	Mar. 31, 2022	Dec. 31, 2021
Maximum | Appraisal Adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreclosed real estate & repossessed assets	0.35	0.35
Maximum | Costs to Sell
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreclosed real estate & repossessed assets	0.15	0.15
Maximum | Changes in property condition
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreclosed real estate & repossessed assets	0.20	0.20
Maximum | Residential | 1-4 family residential | Appraisal Adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.35	0.35
Maximum | Residential | 1-4 family residential | Costs to Sell
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.15	0.15
Maximum | Commercial and industrial | Other loans | Appraisal Adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.35	0.35
Maximum | Commercial and industrial | Other loans | Costs to Sell
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.15	0.15
Maximum | Commercial and industrial | Other loans | Changes in property condition
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.20	0.20
Minimum | Appraisal Adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreclosed real estate & repossessed assets	0.05	0.05
Minimum | Costs to Sell
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreclosed real estate & repossessed assets	0.05	0.05
Minimum | Changes in property condition
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreclosed real estate & repossessed assets	0.10	0.10
Minimum | Residential | 1-4 family residential | Appraisal Adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.05	0.05
Minimum | Residential | 1-4 family residential | Costs to Sell
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.05	0.05
Minimum | Commercial and industrial | Other loans | Appraisal Adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.05	0.05
Minimum | Commercial and industrial | Other loans | Costs to Sell
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.05	0.05
Minimum | Commercial and industrial | Other loans | Changes in property condition
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.10	0.10
Weighted Average | Appraisal Adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreclosed real estate & repossessed assets	0.25	0.25
Weighted Average | Costs to Sell
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreclosed real estate & repossessed assets	0.10	0.10
Weighted Average | Changes in property condition
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreclosed real estate & repossessed assets	0.15	0.15
Weighted Average | Residential | 1-4 family residential | Appraisal Adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.20	0.20
Weighted Average | Residential | 1-4 family residential | Costs to Sell
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.10	0.10
Weighted Average | Commercial and industrial | Other loans | Appraisal Adjustments
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.25	0.25
Weighted Average | Commercial and industrial | Other loans | Costs to Sell
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.10	0.10
Weighted Average | Commercial and industrial | Other loans | Changes in property condition
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	0.15	0.15