Insurance Operations - Gross Written Premiums (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) item	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Insurance Operations
Percentage of direct premiums sourced from distribution party acquired by a third party insurance carrier	7.10%	13.50%
Number of distribution partners contributing the largest amounts of direct written premiums | item	3
Direct premiums written by the largest distribution partners | $	$ 267.8	$ 240.7	$ 235.0