Other Financial Information, Other Income (Expense), Net (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Other Financial Information [Abstract]
Interest income	$ 3.8us-gaap_InvestmentIncomeInterest	$ 2.1us-gaap_InvestmentIncomeInterest
Interest expense	(18.5)us-gaap_InterestExpense	(15.5)us-gaap_InterestExpense
Gain on investments	0.6us-gaap_GainLossOnInvestments	166.2us-gaap_GainLossOnInvestments
Other	(1.7)us-gaap_OtherNonoperatingIncomeExpense	1.4us-gaap_OtherNonoperatingIncomeExpense
Other (expense) income, net	(15.8)us-gaap_NonoperatingIncomeExpense	154.2us-gaap_NonoperatingIncomeExpense
Publicly-traded equity and privately-held investments, net realized gain		$ 163.0

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c),9(a))

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-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

+ Details

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.9)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 9

-Article 9

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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- Definition

This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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-Publisher FASB

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-Name Regulation S-X (SX)

-Number 210

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

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-Name Accounting Standards Codification

-Topic 225

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