Insurance - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020		Mar. 31, 2019
Insurance [Line Items]
Loss and LAE incurred in Neon exited lines	$ 707	[1]	$ 692
Neon Capital Limited
Insurance [Line Items]
Loss and LAE incurred in Neon exited lines	$ 40

[1] Includes $40 million in losses and LAE incurred in the Neon exited lines in the first three months of 2020.