Basis of Presentation (Policies)	9 Months Ended
Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts	We perform analyses to evaluate our premiums receivables for expected credit losses. See the 2020 Annual Report to Shareholders for a discussion on our premiums receivable allowance for credit loss policy.

Disclosure of accounting policy for charging off uncollectible financing receivables, including, but not limited to, factors and methodologies used in estimating the allowance for credit loss.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (a,b)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

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