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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 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 + Details
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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 + Details
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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 + Details
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