Basis of Presentation Basis of Presentation (Revenue Recognition) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement [Line Items]
Net investment income									$ 1,596	$ 1,509	$ 1,576
Premiums									1,426	1,394	1,491
Other revenues									1,249	1,105	1,189
Total revenues									12,924	12,180	11,839
Banking and deposit interest expense									89	48	39
Total net revenues	$ 3,179	$ 3,292	$ 3,196	$ 3,168	$ 3,180	$ 3,014	$ 3,012	$ 2,926	12,835	12,132	11,800
Distribution expenses									3,637	3,397	3,200
Interest credited to fixed accounts									674	656	623
Benefits, claims, losses and settlement expenses									2,302	2,233	2,646
Amortization of deferred acquisition costs									322	267	415
Interest and debt expense									245	207	241
General and administrative expense									3,171	3,158	3,084
Total expenses									10,351	9,918	10,209
Pretax income									2,484	2,214	1,591
Income tax provision									386	734	278
Net income	539	$ 503	$ 462	$ 594	177	$ 507	$ 393	$ 403	2,098	1,480	1,313
Assets	137,216				147,480				137,216	147,480
Liabilities	131,628				141,485				131,628	141,485
Retained earnings	$ (12,909)				(11,326)				(12,909)	(11,326)
Management and financial advice fees [Member]
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									6,776	6,415	5,802
Distribution fees [Member]
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax									$ 1,877	1,757	1,781
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Statement [Line Items]
Other revenues										95	94
Total revenues										105	104
Total net revenues										105	104
Distribution expenses										(2)	(2)
General and administrative expense										107	107
Total expenses										105	105
Pretax income											(1)
Net income											(1)
Assets					10					10	10
Liabilities					13					13	13
Retained earnings					$ (3)					(3)	(3)
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Management and financial advice fees [Member]
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax										23	24
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member] | Distribution fees [Member]
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax										(13)	(14)
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Statement [Line Items]
Net investment income										1,509	1,576
Premiums										1,394	1,491
Other revenues										1,010	1,095
Total revenues										12,075	11,735
Banking and deposit interest expense										48	39
Total net revenues										12,027	11,696
Distribution expenses										3,399	3,202
Interest credited to fixed accounts										656	623
Benefits, claims, losses and settlement expenses										2,233	2,646
Amortization of deferred acquisition costs										267	415
Interest and debt expense										207	241
General and administrative expense										3,051	2,977
Total expenses										9,813	10,104
Pretax income										2,214	1,592
Income tax provision										734	278
Net income										1,480	1,314
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Management and financial advice fees [Member]
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax										6,392	5,778
Calculated under Revenue Guidance in Effect before Topic 606 [Member] | Distribution fees [Member]
Statement [Line Items]
Revenue from Contract with Customer, Including Assessed Tax										$ 1,770	$ 1,795