Investments Gross Realized Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Marketable Securities [Line Items]
Net realized (losses) gains on investments	$ 669	$ 1,194	$ (683)	$ 1,513
Fixed maturity securities
Marketable Securities [Line Items]
Gross realized gains fixed maturity securities	461	365	1,489	959
Gross realized losses fixed maturities	(753)	(375)	(2,150)	(1,283)
Equity securities
Marketable Securities [Line Items]
Gross realized gains equity securities	1,405	1,221	4,276	2,862
Gross realized losses equity securities	$ (444)	$ (17)	$ (4,298)	$ (1,025)

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27357-111563

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117546-209714

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Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

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