Other Assets (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses	$ 7.5	$ 0.9
Ceding commissions receivable	5.4	0.0
Investment income due and accrued	0.9	0.4
Security deposits	0.7	0.5
VAT receivable	0.0	0.2
Funds on deposit with claims administrator	0.0	0.2
Prepaid income taxes	0.0	0.1
Other	0.0	0.2
Total other assets	$ 14.5	$ 2.5