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Investment Securities - Narrative (Details) - security	Jun. 30, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Number of investment securities in unrealized loss position	7	40
Number of investment securities in unrealized loss position longer than 12 months	5
Number of investment securities in unrealized loss position less than 12 months	2

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Marketable Securities In Unrealized Loss Positions, Qualitative Disclosure, Number Of Positions, Less Than 12 Months

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