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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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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.

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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)
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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

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

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-Section 45
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