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Fair Value Measurements (Schedule of Quantitative Information about Level Three Fair Value Measurements - Nonrecurring Basis) (Details) | 12 Months Ended
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Dec. 31, 2020 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value, Discounted Cash Flow, Valuation Techniques | Discounted cash flow |
Mortgage Servicing Rights [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Unobservable Inputs, Loan Servicing Costs, Loans in Foreclosure | $ 1,000 |
Mortgage Servicing Rights [Member] | Minimum [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Unobservable Input, Discount Rate | 9.15% |
Unobservable Input, Prepayment Speed | 13.25% | [1]
Unobservable Input, Loan Servicing Costs, Performing Loans | $ 71 |
Unobservable Input, Loan Servicing Costs, Delinquent Loans | $ 200 |
Mortgage Servicing Rights [Member] | Maximum [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Unobservable Input, Discount Rate | 9.27% |
Unobservable Input, Prepayment Speed | 14.85% | [1]
Unobservable Input, Loan Servicing Costs, Performing Loans | $ 72 |
Unobservable Input, Loan Servicing Costs, Delinquent Loans | $ 750 |
Mortgage Servicing Rights [Member] | Weighted Average [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Unobservable Input, Discount Rate | 9.23% | [1]
Unobservable Input, Prepayment Speed | 14.58% | [1]
Unobservable Input, Loan Servicing Costs, Performing Loans | $ 72 | [1]
[1] | *Ranges and weighted averages based on interest rate tranches.

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