Investments (Details 5) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net realized investment gains (losses)
Net realized investment gains (losses)	$ 0	$ 899	$ (497)	$ 1,539
Available-for-sale securities
Available-for-sale securities:
Gross realized gains	525	1,621	1,100	2,708
Gross realized losses	(526)	(722)	(1,512)	(1,261)
Net realized (losses) gains on available-for-sale securities	(1)	899	(412)	1,447
Equity securities
Equity securities
Equity securities	(1)		(189)
Other investments
Miscellaneous
Miscellaneous	$ 2	$ 0	$ 104	$ 92

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), excluding other-than-temporary impairment (OTTI).

+ References

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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), excluding other-than-temporary impairment (OTTI).

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Amount of unrealized and realized gain (loss) on 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/2009/role/commonPracticeRef
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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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