Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Net investment income
Interest income	$ 2,001	$ 1,010
Dividend income	125	30
Less: investment expense	(91)	(80)
Net investment income	$ 2,035	$ 960

Amount of dividend income on nonoperating securities.

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

+ Details

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Amount of expenses related to the generation of investment income.

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- Definition

Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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