Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

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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.

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- Definition

Fair value of all derivative assets designated as fair value hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959

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- Definition

Amount of income (expense) related to nonoperating activities, classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.9)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Derivative Financial Instruments and Hedging Activities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) Contract	Dec. 31, 2015 USD ($) Contract	Dec. 31, 2014 USD ($)	Apr. 05, 2016 USD ($)
Derivatives, Fair Value [Line Items]
Other non-operating income (deductions)	$ 3.8	$ (2.3)	$ 1.8
Foreign Exchange Forward [Member]
Derivatives, Fair Value [Line Items]
Number of contracts \| Contract	2	0
Other non-operating income (deductions)	$ (0.6)	$ (0.3)
Cash Flow Hedges [Member] \| Foreign Exchange Forward [Member]
Derivatives, Fair Value [Line Items]
Number of contracts \| Contract	2
Cash Flow Hedges [Member] \| Interest Rate Swaps [Member] \| Other Assets and Deferred Charges [Member]
Derivatives, Fair Value [Line Items]
Fair value of derivative asset	$ 2.5
Cash Flow Hedges [Member] \| Designated [Member] \| Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Notional amount	$ 257.0			$ 300.0