Investments (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019 USD ($) security	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) security	Sep. 30, 2018 USD ($)	Dec. 31, 2018 security
Schedule of Available-for-sale Securities [Line Items]
Gross gains on investments	$ 500	$ 300	$ 4,900	$ 900
Gross losses on investments	300	500	500	700
Proceeds from sale of investment securities	$ 6,000	$ 400	13,000	$ 14,600
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Other-than-temporary impairment			$ 0
Debt Securities [Member]
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Number of Positions [Abstract]
Number of debt securities with unrealized loss | security	81		81		328
Number of debt securities with unrealized loss, less than 12 months | security	58		58		221
Number of debt securities with unrealized loss, greater than 12 months | security	23		23		107