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Description of the interest rate for the amounts borrowed under Senior notes due June 2, 2014., including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

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Future date where revolving credit facility maximum capacity changes whether increase or decrease or new capacity amount.

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Amount of letters of credit issued and outstanding under revolving letter of credit facility.

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Amount of current borrowing capacity under the credit facility prior to most recent amendments.

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Percentage of principal amount of outstanding convertible debentures to be redeemed as reported or per contractual agreements.

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Principal amount of debentures to be converted per election by holders under the terms of the debenture agreement.

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Decrease for amounts repaid on the debt instrument for the period.

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Interest rate stated in the contractual debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, which may be presented in a variety of ways (year, month and year, day, month and year, quarter, etc.).

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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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Gross amount of debt extinguished.

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This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

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Balance held at close of period in number of contracts.

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The option price of the investment that is subject to option.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Total of the portions of the carrying amounts as of the balance sheet date of long-term debt, which may include notes payable, bonds payable, debentures, mortgage loans, and commercial paper, which are scheduled to be repaid within one year or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Debt (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2010	Jun. 30, 2011	Jul. 29, 2011	Dec. 31, 2010
Debt Instrument [Line Items]
Principal outstanding amount		$ 1,954.6		$ 1,292.8
Current maturities		(431.0)		(519.9)
Long-term maturities Total		1,523.6		772.9
Total amount of premium paid for common stock call options purchased by a third party financial intermediary		21.9
Percentage of principal amount of outstanding convertible debentures to be redeemed (in hundredths)		100.00%
Principal amount of debentures to be converted into equity per election of holders		295.5
Total cash paid for convertible debentures		181.2
Original amount of borrowing capacity of the Multicurrency Revolving Letter of Credit and Credit Facilities		585.0
Date when revolving credit facility maximum capacity changes		Apr. 14, 2013
Future amount of revolving credit facility maximum capacity after previous period expires		730.0
Senior Notes [Member]
Debt Instrument [Line Items]
Unamortized original issue discount		(4.0)		(1.8)
Senior Notes [Member] \| 6.375% Notes due July 15, 2018
Debt Instrument [Line Items]
Principal outstanding amount		450.0		450.0
Maturity date		Jul. 15, 2018
Interest rate (in hundredths)		6.375%
Senior Notes [Member] \| 4.5% Notes due June 1, 2021
Debt Instrument [Line Items]
Principal outstanding amount		250.0		0
Maturity date		Jun. 01, 2021
Interest rate (in hundredths)		4.50%
Senior Notes [Member] \| 7.0% Notes due July 15, 2038
Debt Instrument [Line Items]
Principal outstanding amount		300.0		300.0
Maturity date		Jul. 15, 2038
Interest rate (in hundredths)		7.00%
Senior Notes [Member] \| 5.95% Notes due June 1, 2041
Debt Instrument [Line Items]
Principal outstanding amount		250.0		0
Maturity date		Jun. 01, 2041
Interest rate (in hundredths)		5.95%
Senior Notes [Member] \| 2.5% Convertable Debenture Notes due June 15, 2026
Debt Instrument [Line Items]
Interest rate (in hundredths)		2.50%
Senior Notes [Member] \| Floating rate Senior Notes due June 2, 2014
Debt Instrument [Line Items]
Principal outstanding amount		250.0		0
Maturity date		Jun. 02, 2014
Floating rate		3 month LIBOR plus 0.0093
Convertible Debt [Member]
Debt Instrument [Line Items]
Unamortized original issue discount		0		(6.9)
Convertible Debt [Member] \| 2.5% Convertable Debenture Notes due June 15, 2026
Debt Instrument [Line Items]
Principal outstanding amount		371.1		500.0
Maturity date		Jun. 15, 2026
Retirement of Debentures		128.9	204.5
Number of common stock call options purchased from a third party financial intermediary (in shares)		5.0
Average strike price of common stock call options purchased by a third party financial intermediary (dollars per share)		47.69
Total amount of premium paid for common stock call options purchased by a third party financial intermediary	21.9
Other Long Term Debt [Member]
Debt Instrument [Line Items]
Principal outstanding amount		71.8		37.5
Obligations Under Capital Leases [Member]
Debt Instrument [Line Items]
Principal outstanding amount		15.7		14.0
Line of Credit [Member]
Line of Credit Facility [Line Items]
Revolving credit facility maximum capacity		835.0
Remaining capacity under revolving line of credit faciility		809.6
Line of Credit Multi Currency [Member]
Line of Credit Facility [Line Items]
Revolving credit facility maximum capacity		250.0
Remaining capacity under revolving line of credit faciility		204.7
Letters of credit outstanding		45.3
loc_Line of Credit [Member]
Line of Credit Facility [Line Items]
Letters of credit outstanding		$ 25.4