Segment Information (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) segment	Sep. 30, 2014 USD ($)
Financial information of the segments
Number of reportable segments | segment			3
Revenues
Premium income	$ 154,017	$ 169,543	$ 374,437	$ 363,893
Fee income	225,242	181,991	688,020	520,509
Other revenue	1,820	0	5,460	0
Net investment income	363,057	292,061	942,082	911,694
Realized investment gains (losses), net	22,551	23,530	56,610	87,495
Total revenues	766,687	667,125	2,066,609	1,883,591
Benefits and expenses:
Policyholder benefits	357,614	361,991	957,603	931,067
Operating expenses	310,792	214,843	870,908	601,995
Total benefits and expenses	668,406	576,834	1,828,511	1,533,062
Income (loss) before income taxes	98,281	90,291	238,098	350,529
Income tax expense	30,708	29,790	78,926	120,324
Net income	67,573	60,501	159,172	230,205
Individual Markets
Revenues
Premium income	132,761	151,831	308,976	302,070
Fee income	19,745	20,781	66,214	71,349
Other revenue	0		0
Net investment income	222,445	181,944	595,757	554,508
Realized investment gains (losses), net	8,304	9,458	20,256	26,182
Total revenues	383,255	364,014	991,203	954,109
Benefits and expenses:
Policyholder benefits	270,614	282,985	725,526	700,694
Operating expenses	49,407	46,463	116,770	123,892
Total benefits and expenses	320,021	329,448	842,296	824,586
Income (loss) before income taxes	63,234	34,566	148,907	129,523
Income tax expense	21,539	11,598	51,262	44,516
Net income	41,695	22,968	97,645	85,007
Empower Retirement
Revenues
Premium income	477	173	493	1,213
Fee income	204,488	160,241	618,841	446,201
Other revenue	1,820		5,460
Net investment income	127,160	96,771	305,969	316,724
Realized investment gains (losses), net	14,247	13,777	36,257	60,933
Total revenues	348,192	270,962	967,020	825,071
Benefits and expenses:
Policyholder benefits	54,401	51,396	151,194	151,397
Operating expenses	242,841	153,970	704,047	433,529
Total benefits and expenses	297,242	205,366	855,241	584,926
Income (loss) before income taxes	50,950	65,596	111,779	240,145
Income tax expense	14,884	21,912	35,651	82,271
Net income	36,066	43,684	76,128	157,874
Other
Revenues
Premium income	20,779	17,539	64,968	60,610
Fee income	1,009	969	2,965	2,959
Other revenue	0		0
Net investment income	13,452	13,346	40,356	40,462
Realized investment gains (losses), net	0	295	97	380
Total revenues	35,240	32,149	108,386	104,411
Benefits and expenses:
Policyholder benefits	32,599	27,610	80,883	78,976
Operating expenses	18,544	14,410	50,091	44,574
Total benefits and expenses	51,143	42,020	130,974	123,550
Income (loss) before income taxes	(15,903)	(9,871)	(22,588)	(19,139)
Income tax expense	(5,715)	(3,720)	(7,987)	(6,463)
Net income	$ (10,188)	$ (6,151)	$ (14,601)	$ (12,676)