Reinsurance (Reinsurance amounts recorded on the Consolidated Statement of Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reinsurance Disclosures [Abstract]
Direct insurance premiums and fee income	$ 9,529	$ 9,064	$ 8,023
Reinsurance assumed	73	7	8
Reinsurance ceded	(1,311)	(1,410)	(1,275)
Total insurance premiums and fee income	8,291	7,661	6,756
Direct insurance benefits	6,420	6,127	5,487
Reinsurance recoveries netted against benefits	(1,376)	(1,448)	(1,625)
Benefits	$ 5,044	$ 4,679	$ 3,862