Goodwill and Other Intangibles (Details 2) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 PBM [Member]	Dec. 31, 2010 PBM [Member]	Dec. 31, 2011 EM [Member]	Dec. 31, 2009 EM [Member]
Summary of change in net carrying value of goodwill by business segment
Beginning Balance	$ 5,486.2	$ 5,497.1	$ 5,405.7	$ 5,416.6	$ 80.5	$ 80.5
Adjustment to purchase price allocation		(17.8)		(17.8)
Foreign currency translation and other	(0.5)	6.9	(0.5)	6.9	0
Ending Balance	$ 5,485.7	$ 5,486.2	$ 5,405.2	$ 5,405.7	$ 80.5	$ 80.5

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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+ Details

- Definition

The increase (decrease) in the recorded value of goodwill for foreign currency translation adjustments and purchase accounting adjustments needed to revise the carrying amount of goodwill to fair value.

+ References

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+ Details