Investments (Major Categories of net Investment Income) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Schedule of Investments [Line Items]
Investment income	$ 21,609	$ 19,203
Investment expenses	(1,005)	(971)
Investment income, net of expenses	20,604	18,232
Cash and Cash Equivalents [Member]
Schedule of Investments [Line Items]
Investment income	766	518
Equity Securities [Member]
Schedule of Investments [Line Items]
Investment income	2,364	1,151
Debt Securities [Member] \| U.S. Treasury Securities and Obligations of U.S. Government [Member]
Schedule of Investments [Line Items]
Investment income	916	902
Debt Securities [Member] \| Corporate Bonds [Member]
Schedule of Investments [Line Items]
Investment income	7,317	6,696
Debt Securities [Member] \| Collateralized Corporate Bank Loans [Member]
Schedule of Investments [Line Items]
Investment income	6,028	5,658
Debt Securities [Member] \| Municipal Bonds [Member]
Schedule of Investments [Line Items]
Investment income	3,907	3,757
Debt Securities [Member] \| Mortgage Backed [Member]
Schedule of Investments [Line Items]
Investment income	$ 311	$ 521

Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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