Investments Contractual maturity periods (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Due in one year of less, Amortized Cost	$ 5,462
Due in one year or less, Estimated Fair Value	5,445
Due after one year through five years, Amortized Cost	5,342
Due after one year through five years, Estimated Fair Value	5,233
Due after five years through ten years, Amortized Cost	217
Due after five years through ten years, Estimated Fair Value	210
Due after ten years, Amortized Cost	1,411
Due after ten years, Estimated Fair Value	1,372
Total fixed maturities Amortized Cost	12,432	$ 14,707
Estimated Fair Value, Fixed Maturities	$ 12,260	$ 14,541