Segment Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($) segment	Mar. 31, 2016 USD ($)
Financial information of the segments
Number of reportable segments | segment	3
Revenues
Premium income	$ 152,241	$ 154,927
Fee income	255,116	225,067
Other revenue	2,384	3,149
Net investment income	313,471	331,785
Realized investment gains (losses), net	(11,754)	31,270
Total revenues	711,458	746,198
Benefits and expenses:
Policyholder benefits	339,428	336,743
Operating expenses	320,083	286,791
Total benefits and expenses	659,511	623,534
Income before income taxes	51,947	122,664
Income tax expense	17,117	24,038
Net income	34,830	98,626
Individual Markets
Revenues
Premium income	131,559	133,286
Fee income	25,981	22,724
Other revenue	0	0
Net investment income	184,205	207,693
Realized investment gains (losses), net	584	11,806
Total revenues	342,329	375,509
Benefits and expenses:
Policyholder benefits	270,088	267,497
Operating expenses	38,386	37,223
Total benefits and expenses	308,474	304,720
Income before income taxes	33,855	70,789
Income tax expense	11,650	23,834
Net income	22,205	46,955
Empower Retirement
Revenues
Premium income	91	346
Fee income	227,320	200,923
Other revenue	2,384	3,149
Net investment income	117,620	110,534
Realized investment gains (losses), net	(12,316)	19,471
Total revenues	335,099	334,423
Benefits and expenses:
Policyholder benefits	47,629	49,917
Operating expenses	255,764	231,640
Total benefits and expenses	303,393	281,557
Income before income taxes	31,706	52,866
Income tax expense	10,426	651
Net income	21,280	52,215
Other
Revenues
Premium income	20,591	21,295
Fee income	1,815	1,420
Other revenue	0	0
Net investment income	11,646	13,558
Realized investment gains (losses), net	(22)	(7)
Total revenues	34,030	36,266
Benefits and expenses:
Policyholder benefits	21,711	19,329
Operating expenses	25,933	17,928
Total benefits and expenses	47,644	37,257
Income before income taxes	(13,614)	(991)
Income tax expense	(4,959)	(447)
Net income	$ (8,655)	$ (544)