Investments - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Schedule of Investments [Line Items]
Investment income	$ 18,365	$ 32,854
Investment expenses	(401)	(832)
Net investment income	17,964	32,022
Fixed maturities
Schedule of Investments [Line Items]
Investment income	12,651	26,220
Funds withheld interest
Schedule of Investments [Line Items]
Investment income	3,853	4,537
Loan to related party
Schedule of Investments [Line Items]
Investment income	1,365	1,822
Cash and cash equivalents and other
Schedule of Investments [Line Items]
Investment income	$ 496	$ 275

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
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