Income Taxes, Valuation Allowance (Details) - NMTC [Member] - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
NMTC Carryforward [Line Items]
Deferred Tax Asset	$ 96.0	$ 95.4
Valuation Allowance	$ 0.0

Amount of deferred tax asset, before valuation allowance, attributable to deductible other tax carryforwards.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 30

-Paragraph 5

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6907311&loc=d3e30536-109315

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from tax credit carryforwards for which it is more likely than not that a tax benefit will not be realized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Valuation Allowance

-URI http://asc.fasb.org/extlink&oid=6528051

+ Details

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Period Type:	instant

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