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Investment Securities - Visa Class B Restricted Shares (Details) - Visa $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) shares | Dec. 31, 2019 USD ($)
Common Class A |  |
Securities |  |
Investment shares owned, if converted | 11,236 |
Common Class B |  |
Securities |  |
Conversion ratio | 1.6228 |
Investment shares owned | 6,924 |
Cost basis | $ | $ 0 | $ 0

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