Reinsurance (Summary of Reinsurance Activity) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Insurance [Abstract]
Net assumed written premiums	$ 23.5	$ 19.1	$ 48.9	$ 36.8
Net premiums earned	19.8	15.4	37.2	29.2
Provision for claims	19.7	12.2	37.6	21.1
Amortization of capitalized acquisition costs	$ 0.5	$ 0.4	$ 1.0	$ 0.8

The amount of expense recognized in the current period that reflects the allocation of capitalized costs associated with acquisition of business. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

Amount of written premiums assumed from other entities.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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-Name Accounting Standards Codification
-Section 50
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- References

No definition available.

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- Definition

Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 220
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- Definition

Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

+ References

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