Segment Information (Total Assets) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Total assets	$ 882,460	$ 902,337
Retail
Segment Reporting Information [Line Items]
Total assets	347,126	359,188
Group, Voluntary & Worksite Benefits
Segment Reporting Information [Line Items]
Total assets	47,443	46,483
Corporate Benefit Funding
Segment Reporting Information [Line Items]
Total assets	227,297	228,543
Latin America
Segment Reporting Information [Line Items]
Total assets	64,949	72,259
Asia
Segment Reporting Information [Line Items]
Total assets	112,456	117,894
Europe, the Middle East and Africa
Segment Reporting Information [Line Items]
Total assets	27,698	29,217
Corporate & Other
Segment Reporting Information [Line Items]
Total assets	$ 55,491	$ 48,753