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Estimated Fair Values (Narrative) (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fair Value, Option, Changes in Fair Value, Gain (Loss) | $ 3,900 | $ 289 | $ 50
Loans Held For Sale |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fair Value Of Items For Which Fair Value Option Was Elected Assets | $ 124,837 | 67,869 |
Loans Held For Sale | 90 days or greater |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fair Value Of Items For Which Fair Value Option Was Elected Assets |  | $ 0 |
Minimum | Discount Rate |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Loans held-for-sale, measurement input | 0.06 | 6 |
Other Real Estate Owned, Measurement Input | 0.07 |  |
Minimum | Effective Interest Rate |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Loans held-for-sale, measurement input |  | 3 |
Maximum | Discount Rate |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Loans held-for-sale, measurement input | 0.10 | 11 |
Other Real Estate Owned, Measurement Input | 0.16 |  |
Maximum | Effective Interest Rate |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Loans held-for-sale, measurement input |  | 7 |
Weighted Average [Member] | Discount Rate |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Loans held-for-sale, measurement input | 0.0763 |  |
Other Real Estate Owned, Measurement Input | 0.0844 |  |
Fair Value, Measurements, Recurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Liability measured at fair value on nonrecurring basis |  | $ 0 |
Fair Value, Measurements, Nonrecurring |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Liability measured at fair value on nonrecurring basis |  | 0 |
Corporate Bond Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 |  | $ (112,600) |

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