Consolidated Statements Of Comprehensive Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010		Sep. 30, 2010	Jun. 30, 2010		Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Revenues:
Premiums											$ 35,106	$ 32,712	$ 29,927
Services											1,360	555	520
Investment income											366	329	296
Total revenues	9,056.0	9,301.0	9,284.0	9,191.0	8,276.0	[1]	8,351.0	8,589.0	[2]	8,380.0	36,832.0	33,596.0	30,743.0
Operating expenses:
Benefits											28,823	27,117	24,784
Operating costs											5,395	4,380	4,014
Depreciation and amortization											270	245	237
Total operating expenses											34,488	31,742	29,035
Income from operations											2,344	1,854	1,708
Interest expense											109	105	106
Income before income taxes	313	699	726	497	174	[1]	622	536	[2]	417	2,235	1,749	1,602
Provision for income taxes											816	650	562
Net income	199	445	460	315	107	[1]	393	340	[2]	259	1,419	1,099	1,040
Basic earnings per common share	$ 1.22	$ 2.71	$ 2.76	$ 1.88	$ 0.64	[1]	$ 2.35	$ 2.02	[2]	$ 1.54	$ 8.58	$ 6.55	$ 6.21
Diluted earnings per common share	$ 1.20	$ 2.67	$ 2.71	$ 1.86	$ 0.63	[1]	$ 2.32	$ 2.00	[2]	$ 1.52	$ 8.46	$ 6.47	$ 6.15
Other comprehensive income, net of tax:
Net unrealized investment gains, net of tax expense of $109 million in 2011, $47 million in 2010, and $131 million in 2009											190	82	230
Less: Reclassification adjustment for net realized gains included in net income, net of tax expense of $4 million in 2011, $2 million in 2010, and $7 million in 2009											(7)	(4)	(13)
Other comprehensive income, net of tax											183	78	217
Comprehensive income											$ 1,602	$ 1,177	$ 1,257

[1] Includes an expense of $139 million ($88 million after tax, or $0.52 per diluted common share) associated with reserve strengthening for our closed block of long-term care policies acquired in connection with the 2007 acquisition of KMG America Corporation as more fully described in Note 17 to the consolidated financial statements.

[2] Includes an expense of $147 million ($93 million after tax, or $0.55 per diluted common share) for the write-down of deferred acquisition costs associated with our individual commercial medical policies as more fully described in Note 17 to the consolidated financial statements.