Condensed Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 1,662	$ 1,138
Investment securities	8,248	8,090
Receivables, less allowance for doubtful accounts of $118 in each of 2014 and 2013:	1,460	950
Other current assets	2,605	2,122
Total current assets	13,975	12,300
Property and equipment, net	1,244	1,218
Long-term investment securities	1,800	1,710
Goodwill	3,699	3,733
Other long-term assets	1,848	1,774
Total assets	22,566	20,735
Current liabilities:
Benefits payable	4,432	3,893
Trade accounts payable and accrued expenses	2,752	1,821
Book overdraft	267	403
Unearned revenues	263	206
Total current liabilities	7,714	6,323
Long-term debt	2,598	2,600
Future policy benefits payable	2,199	2,207
Other long-term liabilities	330	289
Total liabilities	12,841	11,419
Commitments and contingencies
Stockholders' equity:
Preferred stock, $1 par; 10,000,000 shares authorized; none issued	0	0
Common stock, $0.16 2/3 par; 300,000,000 shares authorized; 197,498,599 shares issued at March 31, 2014 and 196,275,506 shares issued at December 31, 2013	33	33
Capital in excess of par value	2,333	2,267
Retained earnings	9,266	8,942
Accumulated other comprehensive income	226	158
Treasury stock, at cost, 42,714,365 shares at March 31, 2014 and 42,245,097 shares at December 31, 2013	(2,133)	(2,084)
Total stockholders' equity	9,725	9,316
Total liabilities and stockholders' equity	$ 22,566	$ 20,735