Investments Gross Realized Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Marketable Securities [Line Items]
Net realized (losses) gains on investments	$ (721)	$ 483	$ (1,352)	$ 319
Fixed maturity securities
Marketable Securities [Line Items]
Gross realized gains fixed maturity securities	139	479	1,028	594
Gross realized losses fixed maturities	(1,096)	(241)	(1,397)	(908)
Equity securities
Marketable Securities [Line Items]
Gross realized gains equity securities	1,295	688	2,871	1,641
Gross realized losses equity securities	$ (1,059)	$ (443)	$ (3,854)	$ (1,008)

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).

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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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