Segment Information (Total Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total assets	$ 7,925,008	$ 7,633,046
Annuities
Segment Reporting Information [Line Items]
Total assets	6,845,321	6,708,803
Life
Segment Reporting Information [Line Items]
Total assets	634,267	342,592
Corporate & Other
Segment Reporting Information [Line Items]
Total assets	$ 445,420	$ 581,651