Fair Value Measurements - Quantitative information about Level 3 measurements for fair value on a recurring basis (Details) - Recurring - Level 3	Dec. 31, 2021 security	Dec. 31, 2020 security
Derivative assets - mortgage | Pull through rate | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	0.459	0.656
Derivative assets - mortgage | Pull through rate | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	1	1
Derivative assets - mortgage | Pull through rate | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	0.872	0.839
Derivative assets - customer derivative positions | Estimated loss rate | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	0.334	1
Derivative assets - customer derivative positions | Estimated loss rate | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	0.440	1
Derivative assets - customer derivative positions | Estimated loss rate | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative assets, measurement input	0.360	1
Corporate bonds | Discount rate | Low
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds, measurement input	0.036
Corporate bonds | Discount rate | High
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds, measurement input	0.038
Corporate bonds | Discount rate | Weighted Average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Corporate bonds, measurement input	0.036