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Reinsurance Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses, beginning of period	$ 1,777	$ 2,396	$ 1,777	$ 4,400
Current period provision for expected credit losses	(182)	(565)	(182)	334
Write-offs charged against the allowance for credit losses	0	0	0	0
Recoveries	0	0	0	0
Allowance for credit losses, end of period	1,595	1,831	1,595	1,831
Reinsurance Recoverable [Domain]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses, beginning of period	1,777	2,396	1,777	1,497
Retained Earnings [Member] | Reinsurance Recoverable [Domain] | Accounting Standards Update 2016-13 [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses, beginning of period	$ 0	$ 0	$ 0	$ (2,903)	[1]
[1] Represents the impact of our adoption of ASU 2016-13, Financial Instruments - Credit Losses.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of the write-down or write-off of a receivable from a reinsurer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount of increase in allowance for credit loss on reinsurance recoverable, from recovery.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount of expense (reversal of expense) for expected credit loss on reinsurance recoverable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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Amount of allowance for credit loss on reinsurance recoverable.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 13
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-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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