Goodwill and Intangible Assets - Goodwill Rollforward (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2021
Goodwill
Beginning balance		$ 43.5
Impairments		0.0
Acquisitions		0.0
Ending balance		43.5
Property & Casualty
Goodwill
Beginning balance		9.5
Impairments		0.0
Acquisitions		0.0
Ending balance		9.5
Supplemental
Goodwill
Beginning balance		19.6
Impairments		0.0
Acquisitions		0.0
Ending balance		19.6
Retirement
Goodwill
Beginning balance		4.5
Impairments	$ (28.0)	0.0
Acquisitions		0.0
Ending balance		4.5
Life
Goodwill
Beginning balance		9.9
Impairments		0.0
Acquisitions		0.0
Ending balance		$ 9.9

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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