Investments - Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2008
Debt and Equity Securities, FV-NI [Line Items]
Gross Gains	$ 0	$ 0
Gross Losses	0	0
Proceeds	0	$ 0
Gain on sale of equity investment securities	$ 1,500
Class B Common Stock \| Bank \| Visa, Inc.
Debt and Equity Securities, FV-NI [Line Items]
Number of shares received in an IPO			7,158

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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