Investment Securities (Visa Class B Restricted Shares Narrative) (Details 8)	3 Months Ended
Mar. 31, 2020 shares
Visa Conversion Rate Swap Agreement
Net Investment Income [Line Items]
Conversion ratio	1.6228
Equity securities remaining, shares	80,214
Visa Class A Unrestricted Securities
Net Investment Income [Line Items]
Equity securities remaining, shares	130,171

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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