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Reinsurance Reinsurance Allowance for Credit Losses (Details) - USD ($) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Allowance for credit losses, beginning of period | [1] | $ 4,400 |  |
Cumulative effect of new accounting principle in period of adoption |  |  | $ 1,435 |
Current period provision for expected credit losses |  | 5 |  |
Write-offs charged against the allowance |  | 0 |  |
Recoveries |  | 0 |  |
Allowance for credit losses, end of period |  | 1,502 |  |
Retained Earnings [Member] | Accounting Standards Update 2016-13 [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Cumulative effect of new accounting principle in period of adoption |  |  | 1,435 | $ 0
Retained Earnings [Member] | Accounting Standards Update 2016-13 [Member] | Reinsurance Recoverable [Domain] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |
Allowance for credit losses, beginning of period | [1] | $ 1,497 |  |
Cumulative effect of new accounting principle in period of adoption | [1] |  | $ (2,903) |
[1] | See Note 2. "Adoption of Accounting Pronouncements" for additional information regarding our adoption of ASU 2016-13.

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- Definition Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption. + References No definition available. + Details
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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=119407570&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=119407570&loc=SL82919249-210447 + Details
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