Summary of Investments - SOI OTTI table (Details) - Fixed maturities - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward]
Beginning balance	$ 62,231	$ 83,665
Due to sales, maturities or payoffs during the period	(1,510)	0
Due to increases in cash flows expected to be collected that are recognized over the remaining life of the security	(7,946)	(3,306)
Ending balance	$ 52,775	$ 80,359