Debt Outstanding Debt (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Principal Outstanding	$ 7,104.8	$ 6,985.0
Fair Value Hedge Accounting Adjustments	33.8	55.0
Unamortized Discount	(14.3)	(12.0)
Debt Obligations - Carrying Value	7,124.3	7,028.0
Less: Short-term obligations and current maturities of long-term obligations	93.1	1,272.8
Long-term Obligations	7,031.2	5,755.2
Commercial Paper [Member]
Debt Instrument [Line Items]
Principal Outstanding	50.0	900.0
Debt Obligations - Carrying Value	50.0	900.0
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Obligations - Carrying Value	7,019.5	6,093.0
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
Senior Notes [Member] \| 2.15% Senior Notes Due 2012 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	2.15%
Debt Instrument, Maturity Year	2012
Principal Outstanding	0	350.0
Senior Notes [Member] \| 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	300.0
Senior Notes [Member] \| 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
Senior Notes [Member] \| 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
Senior Notes [Member] \| 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
Senior Notes [Member] \| 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	900.0
Senior Notes [Member] \| 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	1,000.0
Senior Notes [Member] \| 1.85% Senior Notes Due 2018 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	1.85%
Debt Instrument, Maturity Year	2018
Effective Interest Rate	1.85%
Principal Outstanding	500.0	0
Senior Notes [Member] \| 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
Senior Notes [Member] \| 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	1,000.0
Senior Notes [Member] \| 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	1,100.0
Senior Notes [Member] \| 3.15% Senior Notes Due 2023 [Member]
Debt Instrument [Line Items]
Stated Interest Rate	3.15%
Debt Instrument, Maturity Year	2023
Effective Interest Rate	3.21%
Principal Outstanding	800.0	0
Other Debt [Member]
Debt Instrument [Line Items]
Principal Outstanding	54.8	35.0
Debt Obligations - Carrying Value	$ 54.8	$ 35.0

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

No definition available.

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

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-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

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- Definition

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).

+ References

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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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(5))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

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-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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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.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number APB14-1

-Paragraph 31

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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- Definition

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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.22)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (c)

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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- Definition

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

+ References

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

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-Name FASB Staff Position (FSP)

-Number APB14-1

-Paragraph 31

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

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-Paragraph 8

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 25

-Section 35

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=6439857&loc=d3e75592-113984

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 24

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- Definition

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.

+ References

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