Segment Information (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Segment Information
Member co-share amounts and government subsidies	$ 1,000,000,000	$ 900,000,000	$ 2,000,000,000	$ 1,700,000,000
Write-down of deferred acquisition costs associated with our individual major medical policies		$ 147,500,000		$ 147,500,000