Debt Outstanding Debt (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Debt Instrument [Line Items]
Principal Outstanding	$ 6,985.0	$ 2,103.6
Fair Value Hedge Accounting Adjustments	55.0	37.3
Unamortized Discount	(12.0)	(3.8)
Debt Obligations - Carrying Value	7,028.0	2,137.1
Less: Short-term obligations and current maturities of long-term obligations	1,272.8	105.8
Long-term Obligations	5,755.2	2,031.3
U.S. Commercial Paper Program [Member]
Debt Instrument [Line Items]
Principal Outstanding	900.0	0
3.25% Senior Subordinated Convertible Notes Due 2024 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.25%
Debt Instrument, Maturity Year	2024
Conversion Price	$ 40.20
Principal Outstanding	0	329.3
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Frequency of Periodic Payment	Interest on each of the senior notes is payable semi-annually.
Debt Instrument, Call Feature	Each of the notes may be redeemed at any time at a redemption price of 100% of the principal amount plus a specified make-whole premium plus accrued interest.
2.15% Senior Notes Due 2012 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.15%
Debt Instrument, Maturity Year	2012
Effective Interest Rate	0.93%
Principal Outstanding	350.0	350.0
2.05% Senior Notes Due 2014 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.05%
Debt Instrument, Maturity Year	2014
Effective Interest Rate	1.11%
Principal Outstanding	300.0	0
3.25% Senior Notes due 2014 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.25%
Debt Instrument, Maturity Year	2014
Effective Interest Rate	1.53%
Principal Outstanding	400.0	400.0
3.20% Senior Notes due 2015 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.20%
Debt Instrument, Maturity Year	2015
Effective Interest Rate	1.56%
Principal Outstanding	450.0	450.0
5.00% Senior Notes due 2015 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	5.00%
Debt Instrument, Maturity Year	2015
Effective Interest Rate	5.14%
Principal Outstanding	250.0	250.0
3.20% Senior Notes Due 2016 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.20%
Debt Instrument, Maturity Year	2016
Effective Interest Rate	3.21%
Principal Outstanding	900.0	0
2.25% Senior Notes Due 2016 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.25%
Debt Instrument, Maturity Year	2016
Effective Interest Rate	2.29%
Principal Outstanding	1,000.0	0
4.70% Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	4.70%
Debt Instrument, Maturity Year	2020
Effective Interest Rate	4.70%
Principal Outstanding	300.0	300.0
4.50% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	4.50%
Debt Instrument, Maturity Year	2021
Effective Interest Rate	4.58%
Principal Outstanding	1,000.0	0
3.60% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.60%
Debt Instrument, Maturity Year	2021
Effective Interest Rate	4.29%
Principal Outstanding	1,100.0	0
Other Debt [Member]
Debt Instrument [Line Items]
Principal Outstanding	$ 35.0	$ 24.3

Year in which the debt instrument is required to be fully repaid.

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).

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- Definition

Description of a feature that permits the issuer of the debt to repay or convert it before the stated maturity date (early retirement date). The description may include such items as the call price, the period that the issuer can call the debt, including the earliest call date, and other significant terms of the call feature, which may include the debt holders' ability to convert the debt to equity if the call option is exercised and contingent events that trigger the issuer's ability to call the debt.

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- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Interest rate stated in the contractual debt agreement.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Amount as of the balance sheet date of the unamortized adjustment to the carrying value of an interest-bearing hedged item made under an effective fair value hedge that is amortized upon discontinuation of the fair value hedge.

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year or the normal operating cycle, if longer plus capital lease obligations due to be paid more than one year after the balance sheet date.

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