Investments (Equity Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt and Equity Securities, FV-NI [Line Items]
Equity security	$ 15,845	$ 15,068
Stock Mutual Funds [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity security	3,166	2,906
Bond Mutual Funds [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity security	12,242	11,774
Common stock [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity security	127	94
Non-redeemable Preferred Stock [Member]
Debt and Equity Securities, FV-NI [Line Items]
Equity security	$ 310	$ 294