Segment Information (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016 USD ($) segment	Mar. 31, 2015 USD ($)
Financial information of the segments
Number of reportable segments | segment	3
Revenues
Premium income	$ 154,927	$ 145,703
Fee income	225,067	225,277
Other revenue	3,149	1,820
Net investment income	331,785	358,856
Realized investment gains (losses), net	31,270	18,200
Total revenues	746,198	749,856
Benefits and expenses:
Policyholder benefits	336,743	327,671
Operating expenses	286,791	271,677
Total benefits and expenses	623,534	599,348
Income before income taxes	122,664	150,508
Income tax expense	24,038	51,896
Net income	98,626	98,612
Individual Markets
Revenues
Premium income	133,286	124,962
Fee income	22,724	21,502
Other revenue	0	0
Net investment income	207,693	217,653
Realized investment gains (losses), net	11,806	8,400
Total revenues	375,509	372,517
Benefits and expenses:
Policyholder benefits	267,497	256,323
Operating expenses	37,223	35,941
Total benefits and expenses	304,720	292,264
Income before income taxes	70,789	80,253
Income tax expense	23,834	28,222
Net income	46,955	52,031
Empower Retirement
Revenues
Premium income	346	0
Fee income	200,923	202,821
Other revenue	3,149	1,820
Net investment income	110,534	127,730
Realized investment gains (losses), net	19,471	9,800
Total revenues	334,423	342,171
Benefits and expenses:
Policyholder benefits	49,917	49,045
Operating expenses	231,640	221,030
Total benefits and expenses	281,557	270,075
Income before income taxes	52,866	72,096
Income tax expense	651	24,380
Net income	52,215	47,716
Other
Revenues
Premium income	21,295	20,741
Fee income	1,420	954
Other revenue	0	0
Net investment income	13,558	13,473
Realized investment gains (losses), net	(7)	0
Total revenues	36,266	35,168
Benefits and expenses:
Policyholder benefits	19,329	22,303
Operating expenses	17,928	14,706
Total benefits and expenses	37,257	37,009
Income before income taxes	(991)	(1,841)
Income tax expense	(447)	(706)
Net income	$ (544)	$ (1,135)