Acquisition of Metromile - Schedule of Recognized Identified Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions	Jul. 28, 2022	Mar. 31, 2023	Dec. 31, 2022
Liabilities assumed
Goodwill		$ 19.0	$ 19.0
Metromile
Assets acquired
Fixed maturities, available for sale, at fair value	$ 1.8
Short-term investments	64.2
Cash, cash equivalents and restricted cash	98.8
Premiums receivable	17.4
Reinsurance recoverable	14.5
Property and equipment	4.6
Value of business acquired ("VOBA")	1.7
Other assets	14.7
Total assets acquired	253.2
Liabilities assumed
Unpaid loss and loss adjustment expenses	84.4
Unearned premium	15.1
Trade payables	0.8
Ceded premium payable	12.0
Other liabilities and accrued expenses	22.2
Total liabilities assumed	134.5
Total identifiable net assets acquired	118.7
Total purchase consideration	137.7
Goodwill	19.0
Metromile | Technology
Assets acquired
Intangible asset	28.0
Metromile | Insurance licenses
Assets acquired
Intangible asset	$ 7.5