Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 1,306	$ 1,377
Investment securities	8,001	7,743
Receivables, less allowance for doubtful accounts of $94 in 2012 and $85 in 2011:	733	1,034
Other current assets	1,670	1,027
Total current assets	11,710	11,181
Property and equipment, net	1,098	912
Long-term investment securities	1,846	1,710
Goodwill	3,640	2,740
Other long-term assets	1,685	1,165
Total assets	19,979	17,708
Current liabilities:
Benefits payable	3,779	3,754
Trade accounts payable and accrued expenses	2,042	1,783
Book overdraft	324	306
Unearned revenues	230	213
Total current liabilities	6,375	6,056
Long-term debt	2,611	1,659
Future policy benefits payable	1,858	1,663
Other long-term liabilities	288	267
Total liabilities	11,132	9,645
Commitments and contingencies (Note 15)
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; 194,470,820 shares issued in 2012 and 193,230,310 shares issued in 2011	32	32
Capital in excess of par value	2,101	1,938
Retained earnings	7,881	6,825
Accumulated other comprehensive income	386	303
Treasury stock, at cost, 36,138,955 shares in 2012 and 29,225,996 shares in 2011	(1,553)	(1,035)
Total stockholders' equity	8,847	8,063
Total liabilities and stockholders' equity	$ 19,979	$ 17,708