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Fair Value - Recurring Fair Value Measures (Details) (USD $) In Millions, unless otherwise specified | 6 Months Ended |
--- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Dec. 31, 2012
Investments [Abstract] |  |  |
Cash Equivalents | $ 24.4 |  | $ 20.7
Fair Value [Abstract] |  |  |
Fair Value Activity in Level 3 | 0 | 0 |
Fair Value Hierarchy Transfers, All Levels | 0 | 0 |
Recurring Fair Value Measurements [Member] |  |  |
Investments [Abstract] |  |  |
Available-for-sale - Equity Securities | 11.9 |  | 18.0
Available-for-sale - Corporate Debt Securities | 8.5 |  | 8.8
Cash Equivalents | 24.4 |  | 20.7
Total Fair Value of Assets | 44.8 |  | 47.5
Liabilities [Abstract] |  |  |
Deferred Compensation | 15.7 |  | 14.0
Derivatives - Interest Rate Swap | 0.5 |  | 0.7
Total Fair Value of Liabilities | 16.2 |  | 14.7
Total Net Fair Value of Assets (Liabilities) | 28.6 |  | 32.8
Recurring Fair Value Measurements [Member] | Level 1 [Member] |  |  |
Investments [Abstract] |  |  |
Available-for-sale - Equity Securities | 11.9 |  | 18.0
Available-for-sale - Corporate Debt Securities | 0 |  | 0
Cash Equivalents | 24.4 |  | 20.7
Total Fair Value of Assets | 36.3 |  | 38.7
Liabilities [Abstract] |  |  |
Deferred Compensation | 0 |  | 0
Derivatives - Interest Rate Swap | 0 |  | 0
Total Fair Value of Liabilities | 0 |  | 0
Total Net Fair Value of Assets (Liabilities) | 36.3 |  | 38.7
Recurring Fair Value Measurements [Member] | Level 2 [Member] |  |  |
Investments [Abstract] |  |  |
Available-for-sale - Equity Securities | 0 |  | 0
Available-for-sale - Corporate Debt Securities | 8.5 |  | 8.8
Cash Equivalents | 0 |  | 0
Total Fair Value of Assets | 8.5 |  | 8.8
Liabilities [Abstract] |  |  |
Deferred Compensation | 15.7 |  | 14.0
Derivatives - Interest Rate Swap | 0.5 |  | 0.7
Total Fair Value of Liabilities | 16.2 |  | 14.7
Total Net Fair Value of Assets (Liabilities) | (7.7) |  | (5.9)
Recurring Fair Value Measurements [Member] | Level 3 [Member] |  |  |
Investments [Abstract] |  |  |
Available-for-sale - Equity Securities | 0 |  | 0
Available-for-sale - Corporate Debt Securities | 0 |  | 0
Cash Equivalents | 0 |  | 0
Total Fair Value of Assets | 0 |  | 0
Liabilities [Abstract] |  |  |
Deferred Compensation | 0 |  | 0
Derivatives - Interest Rate Swap | 0 |  | 0
Total Fair Value of Liabilities | 0 |  | 0
Total Net Fair Value of Assets (Liabilities) | $ 0 |  | $ 0

X
- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. + References No definition available. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represeent Available-for-sale Securities which consist of all investments in certain equity securities neither classified as trading or held-to-maturity securities. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options and put options, but do not include convertible debt. + References No definition available. + Details
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- Definition This element represents the portion of the balance sheet assertion, Deferred Compensation, valued at fair value by the entity. + References No definition available. + Details
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- Definition Fair Value Activity in Level 3 + References No definition available. + Details
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- Definition The amount of transfers in and out of levels 1, 2 and 3 of the fair value hierarchy during the period. + References No definition available. + Details
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- Definition This element represents the portion of the balance sheet Investments line item's cash and cash equivalents, valued at fair value by the entity. + References No definition available. + Details
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13495-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226008-175313 + Details
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- Definition Fair value of asset after deduction of liability. + References No definition available. + Details
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- Definition Fair value of financial and nonfinancial obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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