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Securities (Narrative) (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) security issuance shares | Dec. 31, 2019 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |
Number Of Issuances Of Securities Exceeding Shareholders Equity Threshold | issuance | 0 |
Accrued Interest Receivable for securities |  | $ 46,839
Visa Class B shares, shares sold | shares | 17,360 |
Visa Class B shares, gain on sale | $ 3,000 |
Visa Class B shares, remaining shares | shares | 77,683 |
Equity Securities without Readily Determinable Fair Value, Amount | $ 13,425 | 0
Other Securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Issuances Of Securities Exceeding Shareholders Equity Threshold, Percent | 10.00% |
Available-for-sale Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Accrued Interest Receivable for securities | $ 17,100 | $ 13,900
U.S. Government Agency and Government-Sponsored Enterprise Mortgage-Backed Securities and Collateralized Mortgage Obligations |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 78 |
Asset-backed Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 12 |
Municipal Bonds [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Accrued Interest Receivable for securities | $ 54,831 |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 23 |
US Government Corporations and Agencies Securities [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security | 3 |

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