Reinsurance - Impact of Reinsurance (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Premium written:
Direct	$ 214.4	$ 115.8	$ 46.8
Ceded	(171.7)	(11.2)	(5.6)
Net premium written	42.7	104.6	41.2
Premium earned:
Direct	158.7	75.5	25.3
Ceded	(81.4)	(11.7)	(4.1)
Net premium earned	77.3	63.8	21.2
Loss and LAE incurred:
Direct	113.4	59.7	28.6
Ceded	(58.7)	(13.9)	(13.4)
Net loss and LAE incurred	$ 54.7	$ 45.8	$ 15.2

Amount of earned premiums ceded to other entities.

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