General - Allowance for Credit Losses on Reinsurance Recoverables (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 0	$ 88	$ 91	$ 0
Provision during the period for expected credit losses	0	(30)	(91)	(101)
Write-off amounts during the period	0	0	0	0
Recoveries during the period of amounts previously written off	0	0	0	0
Ending balance	0	58	0	58
Cumulative Effect, Period Of Adoption, Adjustment [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Beginning balance	0	0	0	159
Cumulative Effect, Period Of Adoption, Adjusted Balance [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 0	$ 88	$ 91	$ 159

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

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Period Type:	duration

- Definition

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

+ References

+ Details

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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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of allowance for 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 (a)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446

+ Details

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- Details

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- Details

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