Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Disclosure [Abstract]
U.S. federal income tax rate	35.00%	35.00%	35.00%
Decreases in interest and penalty obligations	$ 0.1	$ 0.2	$ 0.1
Interest obligations	1.2	0.9
Tax-effected unrecognized benefits	$ 0.4

Amount of change in interest expense for an underpayment of income taxes

No definition available.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

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-Subparagraph (SAB TOPIC 6.I)

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- Definition

Amount of interest expense accrued for an underpayment of income taxes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (b)

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