Investments (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Available-for-sale securities
Investment in available-for-sale equity securities	$ 654.0
Proceeds from sale of investments	334.4	375.8	256.3
Gross realized gains	195.3	151.7	27.5
Gross realized losses	2.3	3.6	5.7
Unrealized losses related to other than temporary investment impairments	1.4	2.4	3.8
Investments	881.3	922.1
Other-than temporary impairment
Lower of cost or market valuation adjustments on cost method investments	0.6	8.3	1.7
Cost method, private equity and other investments
Other-than temporary impairment
Cash dividend received		48.4
Cash proceeds on sale of investments		138.7
Gain realized on sale of investments		187.1
State Street Corporation
Available-for-sale securities
Investment in available-for-sale equity securities, number of shares held	7.0
Proceeds from sale of investments	148.8
Gross realized gains	130.3
Number of shares sold	2.3
Private equity funds
Available-for-sale securities
Investments	167.3	231.4
Future capital commitments related to private equity fund investments	$ 6.8

The number of shares of available-for-sale equity securities sold by the entity.

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Available-for-sale Securities, Equity Securities, Number of Shares Held

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No definition available.

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Represents the entity's future capital commitments related to a limited partner investment.

+ References

No definition available.

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Amount of equity securities categorized neither as held-to-maturity nor as trading.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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-SubTopic 320

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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-Publisher FASB

-Name Accounting Standards Codification

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The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

+ References

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 20

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-Paragraph 1

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For investments in debt and equity securities accounted for at cost, the excess of net sale proceeds over the carrying amount of investments disposed of during the period.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph c, d

-Article 5

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-Paragraph 2

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Amount of dividend 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

-Section 03

-Paragraph 7

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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The amount of other than temporary impairment losses on investments in debt and equity securities categorized as Available-for-sale which have been recognized in earnings during the period. Such impairment losses consist of other than temporary impairments (OTTI) on equity securities, credit losses on investments in debt securities, and when the entity intends to sell an impaired debt security or it is more likely than not that the entity will be required to sell the impaired debt security before recovery of its amortized cost basis.

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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- Definition

The cash inflow from sales of all investments, including securities and other assets, having ready marketability and intended by management to be liquidated, if necessary, beyond the current operating cycle.

+ References

No definition available.

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