Condensed Consolidated Statements Of Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues:
Premiums	$ 12,955	$ 13,371	$ 39,556	$ 40,461
Services	223	227	706	749
Investment income	104	96	316	291
Total revenues	13,282	13,694	40,578	41,501
Operating expenses:
Benefits	10,642	10,900	32,857	33,806
Operating costs	1,688	1,739	4,694	5,172
Merger termination fee and related costs, net	0	20	(947)	81
Depreciation and amortization	94	86	278	263
Total operating expenses	12,424	12,745	36,882	39,322
Income (loss) from operations	858	949	3,696	2,179
Interest expense	59	47	166	141
Income (loss) before income taxes	799	902	3,530	2,038
Provision for income taxes	300	452	1,266	1,023
Net income	$ 499	$ 450	$ 2,264	$ 1,015
Basic earnings per common share (in dollars per share)	$ 3.46	$ 3.01	$ 15.56	$ 6.80
Diluted earnings per common share (in dollars per share)	3.44	2.98	15.44	6.73
Dividends per common share (in dollars per share)	$ 0.4	$ 0.29	$ 1.2	$ 0.87