Investments - Schedule of Amortized Cost and Fair Value by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Amortized Cost
Due in one year or less	$ 9,584	$ 30,920
Due after one year through five years	130,223	167,201
Due after five years through ten years	19,508	32,805
Due after ten years	128,039	13,522
Asset-backed securities	45,634	41,912
Amortized Cost	332,988	286,360
Fair Value
Due in one year or less	9,602	30,836
Due after one year through five years	131,952	166,366
Due after five years through ten years	20,125	32,185
Due after ten years	129,495	13,524
Asset-backed securities	44,018	40,652
Fair Value	$ 335,192	$ 283,563