Financial Instruments (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Marketable Securities including Strategic Investments
Fair Value	$ 2,293.7	$ 1,191.2
Gross Unrealized Gains	3.2	3.5
Gross Unrealized Losses	(2.6)	(1.3)
Amortized Cost	2,293.1	1,189.0
Corporate debt securities Current [Member]
Marketable Securities including Strategic Investments
Fair Value	141.8	93.2
Gross Unrealized Gains	0.2	0.1
Gross Unrealized Losses	(0.1)	0
Amortized Cost	141.7	93.1
Corporate debt securities Non-current [Member]
Marketable Securities including Strategic Investments
Fair Value	400.8	219.8
Gross Unrealized Gains	1.2	2.1
Gross Unrealized Losses	(1.2)	(0.5)
Amortized Cost	400.8	218.2
Government securities Current [Member]
Marketable Securities including Strategic Investments
Fair Value	800.5	352.8
Gross Unrealized Gains	0.2	0.2
Gross Unrealized Losses	(0.1)	0
Amortized Cost	800.4	352.6
Government securities Non-current [Member]
Marketable Securities including Strategic Investments
Fair Value	681.5	432.5
Gross Unrealized Gains	1.1	0.6
Gross Unrealized Losses	(0.3)	(0.6)
Amortized Cost	680.7	432.5
Mortgage and other asset backed securities Current [Member]
Marketable Securities including Strategic Investments
Fair Value	2.1	2.1
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Amortized Cost	2.1	2.1
Mortgage and other asset backed securities Non-current [Member]
Marketable Securities including Strategic Investments
Fair Value	267.0	90.8
Gross Unrealized Gains	0.5	0.5
Gross Unrealized Losses	(0.9)	(0.2)
Amortized Cost	267.4	90.5
Other strategic investments Non-current [Member]
Marketable Securities including Strategic Investments
Gross Unrealized Gains	0	17.5
Gross Unrealized Losses	(0.1)	0
Amortized Cost	1.3	27.3
Strategic investments, non-current Fair Value	$ 1.2	$ 44.8

Equity securities categorized neither as held-to-maturity nor trading which are intended be sold more than one year from the balance sheet date or operating cycle, if longer.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6379932&loc=d3e22054-111558

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 22

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 16

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-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 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26626-111562

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 3

-Subparagraph c

-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 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 86-40

-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 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13, 17

-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.

+ Details