Fair Value Measurements (Changes in the Balances of Level 3 Financial Liabilities) (Details) (Embedded contractual derivative liability [Member], USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2013
Embedded contractual derivative liability [Member]
Changes in Level 3 Financial Liabilities
Opening balance	$ 4.2	$ 3.2
Transfers Into Level 3	0	0
Transfers out of Level 3	0	0
Realized in net income	0.6	1.6
Unrealized in accumulated other comprehensive income	0	0
Purchases, issues, sales and settlements:
Purchases	0	0
Issues	0	0
Sales	0	0
Settlements	0	0
Closing balance	$ 4.8	$ 4.8

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Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

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Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sales of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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