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Investment Securities (Narrative) (Details) $ in Millions	Mar. 31, 2021 USD ($) Investments	Dec. 31, 2020 Investments
Investment Securities (Textual)
Fair market value, less than 12 months, number of investments | Investments	39	26
Fair market value, less than 12 months | $	$ 41.1
Fair market value, 12 months or longer, number of investments | Investments	5
Fair market value, 12 months or longer | $	$ 3.7

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Investment securities.

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Investments with fair market value in continuous unrealized loss position for less than twelve months.

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Investments with fair market value In continuous unrealized loss position twelve months or longer.

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Number of investment in continuous unrealized loss position twelve months or longer.

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Number of investments in continuous unrealized loss position, less than twelve months.

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