Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current assets:
Cash and cash equivalents	$ 1,377	$ 1,673
Investment securities	7,743	6,873
Receivables, less allowance for doubtful accounts of $85 in 2011 and $52 in 2010:	1,034	959
Other current assets	1,027	632
Total current assets	11,181	10,137
Property and equipment, net	912	815
Long-term investment securities	1,710	1,500
Goodwill	2,740	2,568
Other long-term assets	1,165	1,083
Total assets	17,708	16,103
Current liabilities:
Benefits payable	3,754	3,469
Trade accounts payable and accrued expenses	1,783	1,681
Book overdraft	306	409
Unearned revenues	213	185
Total current liabilities	6,056	5,744
Long-term debt	1,659	1,669
Future policy benefits payable	1,663	1,493
Other long-term liabilities	267	273
Total liabilities	9,645	9,179
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; 193,230,310 shares issued in 2011 and 190,244,741 shares issued in 2010	32	32
Capital in excess of par value	1,938	1,737
Retained earnings	6,825	5,529
Accumulated other comprehensive income	303	120
Treasury stock, at cost, 29,225,996 shares in 2011 and 21,795,051 shares in 2010	(1,035)	(494)
Total stockholders' equity	8,063	6,924
Total liabilities and stockholders' equity	$ 17,708	$ 16,103