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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
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-Section 55
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Name:	us-gaap_Goodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Goodwill
Goodwill	$ 43.5	$ 43.5
Property and Casualty
Goodwill
Goodwill	9.5
Supplemental
Goodwill
Goodwill	19.6
Retirement
Goodwill
Goodwill	4.5
Life
Goodwill
Goodwill	$ 9.9