Aquisitions (Narrative) (Details) $ in Thousands, € in Millions	1 Months Ended			3 Months Ended		6 Months Ended
	Feb. 28, 2015 USD ($)	Dec. 31, 2014 USD ($)	Jul. 31, 2014 USD ($)	Dec. 31, 2014 EUR (€)	Dec. 31, 2014 USD ($)	Jun. 30, 2015 USD ($)	Dec. 01, 2014 USD ($)
Business Acquisition [Line Items]
Acquisition of commercial assets						$ 5,479
Amortizable intangible assets		$ 37,900			$ 37,900
Goodwill		93,733			93,733	92,976
Estimated fair value of receivables acquired		26,000			26,000
Gross contractual amount of receivables acquired		27,000			27,000
Acquired intangible assets subject to amortization		37,900			37,900
Acquired indefinite-lived intangible assets		$ 4,200			$ 4,200
TherMark Holdings, Inc. [Member]
Business Acquisition [Line Items]
Acquisition of commercial assets	$ 5,500
Amortizable intangible assets						4,600
Goodwill						2,500
Deferred tax liabilities						1,700
Net working capital						100
Acquired intangible assets subject to amortization						$ 4,600
Ferro Coatings Italy S.R.L. [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired		100.00%			100.00%
Vetriceramici S.p.A. [Member]
Business Acquisition [Line Items]
Goodwill							$ 32,431
Net working capital							$ 27,055
Business acquisition, percentage of voting interests acquired		100.00%			100.00%
Acquisition of Vetriceramici | €				€ 87.2
Vetriceramici S.p.A. [Member] | Foreign Currency Change In Euro [Member]
Business Acquisition [Line Items]
Acquisition of Vetriceramici					$ 108,900
Reseller Of Porcelain Enamel Products In Turkey [Member]
Business Acquisition [Line Items]
Acquisition of commercial assets			$ 6,700
Customer Relationships [Member]
Business Acquisition [Line Items]
Amortizable intangible assets		$ 27,800			27,800
Acquired intangible assets subject to amortization		$ 27,800			27,800
Estimated Economic Life		20 years
Technologiical Know-how And Other [Member]
Business Acquisition [Line Items]
Amortizable intangible assets		$ 10,100			10,100
Acquired intangible assets subject to amortization		$ 10,100			10,100
Estimated Economic Life		10 years
Performance Coatings [Member]
Business Acquisition [Line Items]
Goodwill		$ 31,400			31,400
Performance Colors And Glass [Member]
Business Acquisition [Line Items]
Goodwill		$ 1,000			$ 1,000