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Fair Value Accounting and Measurement (Financial Assets Accounted For Fair Value On Nonrecurring Basis) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Equity Securities without Readily Determinable Fair Value, Amount | $ 13,425 | $ 0 |
Fair Value, Option, Changes in Fair Value, Gain (Loss) | (508) | 0 | $ 0
Fair Value, Nonrecurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Collateral dependent loans, Fair Value | 15,569 | 10,007 |
Other real estate owned, fair value disclosure | 525 |  |
Equity Securities without Readily Determinable Fair Value, Amount | 13,425 |  |
Fair Value, Inputs, Level 1 | Fair Value, Nonrecurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Collateral dependent loans, Fair Value | 0 | 0 |
Other real estate owned, fair value disclosure | 0 |  |
Equity Securities without Readily Determinable Fair Value, Amount | 0 |  |
Fair Value, Inputs, Level 2 | Fair Value, Nonrecurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Collateral dependent loans, Fair Value | 0 | 0 |
Other real estate owned, fair value disclosure | 0 |  |
Equity Securities without Readily Determinable Fair Value, Amount | 13,425 |  |
Fair Value, Inputs, Level 3 | Fair Value, Nonrecurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Collateral dependent loans, Fair Value | 15,569 | 10,007 |
Other real estate owned, fair value disclosure | 525 |  |
Equity Securities without Readily Determinable Fair Value, Amount | 0 |  |
Collateral dependent loans [Domain] | Fair Value, Nonrecurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fair Value, Option, Changes in Fair Value, Gain (Loss) | 8,700 | $ 7,519 |
Other real estate owned | Fair Value, Nonrecurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fair Value, Option, Changes in Fair Value, Gain (Loss) | 70 |  |
equity securities without readily determinable fair value [Domain] | Fair Value, Nonrecurring [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Fair Value, Option, Changes in Fair Value, Gain (Loss) | $ (13,425) |  |

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