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Reinsurance (Cumulative Incurred Claims) (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cumulative Incurred Claims [Line Items]
Cumulative Incurred Claims	$ 142,300,000
Claims Reserve	$ 2,300,000
Cumulative Number Of Reported Claims	119,801
Incident Year 2016 [Member]
Cumulative Incurred Claims [Line Items]
Cumulative Incurred Claims	$ 26,000,000.0	$ 26,000,000.0	$ 26,000,000.0	$ 26,000,000.0	$ 25,700,000
Claims Reserve	$ 0
Cumulative Number Of Reported Claims	25,215
Incident Year 2017 [Member]
Cumulative Incurred Claims [Line Items]
Cumulative Incurred Claims	$ 22,600,000	22,600,000	22,500,000	$ 22,300,000
Claims Reserve	$ 0
Cumulative Number Of Reported Claims	20,462
Incident Year 2018 [Member]
Cumulative Incurred Claims [Line Items]
Cumulative Incurred Claims	$ 25,800,000	25,700,000	$ 25,800,000
Claims Reserve	$ 0
Cumulative Number Of Reported Claims	22,309
Incident Year 2019 [Member]
Cumulative Incurred Claims [Line Items]
Cumulative Incurred Claims	$ 30,200,000	$ 30,100,000
Claims Reserve	$ 0
Cumulative Number Of Reported Claims	24,411
Incident Year 2020 [Member]
Cumulative Incurred Claims [Line Items]
Cumulative Incurred Claims	$ 37,700,000
Claims Reserve	$ 2,300,000
Cumulative Number Of Reported Claims	27,404

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Estimated costs as of the balance sheet date of settling insured claims and costs incurred in the claims settlement process for claims that have not yet been submitted to the insurance company for reimbursement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.W)
-URI http://asc.fasb.org/extlink&oid=27015833&loc=d3e570705-122907

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Costs of settling insured claims and costs incurred in the claims settlement process for the specified year specifically for claims that have already been submitted to the insurance company for reimbursement.

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Number of pending claims pertaining to a loss contingency.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

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