Goodwill And Other Acquired Intangible Assets (Activity In Goodwill) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2012	Dec. 31, 2011
Goodwill [Line Items]
Beginning Balance	$ 642.9	$ 465.5
Additions/adjustments	2.1	198.5
FX translation	11.3	(21.1)
Ending balance	656.3	642.9
MIS [Member]
Goodwill [Line Items]
Beginning Balance	11.0	11.4
FX translation	0.2	(0.4)
Ending balance	11.2	11.0
MA [Member]
Goodwill [Line Items]
Beginning Balance	631.9	454.1
Additions/adjustments	2.1	198.5
FX translation	11.1	(20.7)
Ending balance	$ 645.1	$ 631.9

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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- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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