Financial Instruments and Risk Management (Schedule of Available-for-sale Securities Reconciliation) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 27.7	$ 26.5
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0.5	0.5
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Fair Value	28.2us-gaap_AvailableForSaleSecurities	27.0us-gaap_AvailableForSaleSecurities
Debt securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	27.7	26.5
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0.4	0.3
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Fair Value	28.1	26.8
Equity securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0.1	0.2
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Fair Value	$ 0.1	$ 0.2

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

-Publisher FASB

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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

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-Section S99

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