Investment Securities (Narrative) (Details) $ in Millions	Jun. 30, 2020 USD ($) Investments	Dec. 31, 2019 Investments
Investment Securities (Textual)
Fair market value, less than 12 months, number of investments | Investments	11	28
Fair market value, less than 12 months | $	$ 10.9
Fair market value, 12 months or longer, number of investments | Investments	9
Fair market value, 12 months or longer | $	$ 9.4