Investments - Fixed Maturities by Contractual Maturity Periods (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Amortized Cost
Due in one year or less	$ 11,652
Due after one year through five years	7,641
Due after five years through ten years	194
Due after ten years	1,284
Amortized Cost	20,771	$ 12,432
Estimated Fair Value
Due in one year or less	11,672
Due after one year through five years	7,650
Due after five years through ten years	192
Due after ten years	1,273
Estimated Fair Value, Fixed Maturities	$ 20,787	$ 12,260