Derivative Financial Instruments (Summary of Amount of Gain (Loss) Recognized in Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) Gain Recognized in AOCI (Effective Portion)	$ 3.7	$ 0.3
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(1.2)	0.3
Continuing Operations [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(1.1)	0.3
Discontinued Operations [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(0.1)
Natural Gas Commodity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) Gain Recognized in AOCI (Effective Portion)		(0.5)
Natural Gas Commodity Contracts [Member] \| Cost Of Goods Sold [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(0.4)	0.1
Foreign Exchange Contracts - Purchases [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) Gain Recognized in AOCI (Effective Portion)	0.1	(0.5)
Foreign Exchange Contracts - Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) Gain Recognized in AOCI (Effective Portion)	0.3	(0.2)
Foreign Exchange Contracts - Sales [Member] \| Net Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(0.2)	0.2
Interest Rate Swap Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Loss) Gain Recognized in AOCI (Effective Portion)	3.3	$ 1.5
Interest Rate Swap Contracts [Member] \| Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	$ (0.5)

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as 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 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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