Segment Information (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) segment	Jun. 30, 2014 USD ($)
Financial information of the segments
Number of reportable segments | segment			3
Revenues
Premium income	$ 74,717	$ 62,496	$ 220,420	$ 194,350
Fee income	237,501	172,005	462,778	338,518
Other revenue	1,820	0	3,640	0
Net investment income	220,169	319,610	579,025	619,633
Realized investment gains (losses), net	15,859	37,056	34,059	63,965
Total revenues	550,066	591,167	1,299,922	1,216,466
Benefits and expenses:
Policyholder benefits	272,319	262,696	599,990	569,075
Operating expenses	288,441	213,338	560,116	387,154
Total benefits and expenses	560,760	476,034	1,160,106	956,229
Income (loss) before income taxes	(10,694)	115,133	139,816	260,237
Income tax (benefit) expense	(3,679)	40,180	48,218	90,534
Net (loss) income	(7,015)	74,953	91,598	169,703
Individual Markets
Revenues
Premium income	51,253	37,461	176,215	150,239
Fee income	24,967	26,938	46,469	50,567
Other revenue	0		0
Net investment income	155,658	187,044	373,311	372,564
Realized investment gains (losses), net	3,552	9,987	11,952	16,723
Total revenues	235,430	261,430	607,947	590,093
Benefits and expenses:
Policyholder benefits	198,590	178,712	454,914	417,708
Operating expenses	31,424	42,091	67,363	77,431
Total benefits and expenses	230,014	220,803	522,277	495,139
Income (loss) before income taxes	5,416	40,627	85,670	94,954
Income tax (benefit) expense	1,501	13,953	29,724	32,917
Net (loss) income	3,915	26,674	55,946	62,037
Empower Retirement
Revenues
Premium income	16	469	16	1,040
Fee income	211,532	144,079	414,353	285,961
Other revenue	1,820		3,640
Net investment income	51,079	118,778	178,809	219,953
Realized investment gains (losses), net	12,211	27,003	22,011	47,156
Total revenues	276,658	290,329	618,829	554,110
Benefits and expenses:
Policyholder benefits	47,748	51,520	96,792	100,001
Operating expenses	240,176	155,573	461,206	279,559
Total benefits and expenses	287,924	207,093	557,998	379,560
Income (loss) before income taxes	(11,266)	83,236	60,831	174,550
Income tax (benefit) expense	(3,614)	29,049	20,766	60,359
Net (loss) income	(7,652)	54,187	40,065	114,191
Other
Revenues
Premium income	23,448	24,566	44,189	43,071
Fee income	1,002	988	1,956	1,990
Other revenue	0		0
Net investment income	13,432	13,788	26,905	27,116
Realized investment gains (losses), net	96	66	96	86
Total revenues	37,978	39,408	73,146	72,263
Benefits and expenses:
Policyholder benefits	25,981	32,464	48,284	51,366
Operating expenses	16,841	15,674	31,547	30,164
Total benefits and expenses	42,822	48,138	79,831	81,530
Income (loss) before income taxes	(4,844)	(8,730)	(6,685)	(9,267)
Income tax (benefit) expense	(1,566)	(2,822)	(2,272)	(2,742)
Net (loss) income	$ (3,278)	$ (5,908)	$ (4,413)	$ (6,525)