Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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No definition available.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisitions, Goodwill And Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands			1 Months Ended						6 Months Ended
	Jun. 30, 2017	Feb. 01, 2017	Jun. 30, 2018	Feb. 28, 2018	Jan. 31, 2018	Jun. 30, 2017	May 31, 2017	Feb. 28, 2017	Jun. 30, 2018
Business Acquisition [Line Items]
Change in goodwill									$ 501
STLA
Business Acquisition [Line Items]
Percentage of interests acquired			100.00%						100.00%
Cash consideration			$ 14,845
STLA \| Customer Relationships
Business Acquisition [Line Items]
Acquired intangible assets useful life			15 years
Hehr
Business Acquisition [Line Items]
Cash consideration				$ 50,125
Hehr \| Customer Relationships
Business Acquisition [Line Items]
Acquired intangible assets useful life				15 years
Metallarte S.r.l.
Business Acquisition [Line Items]
Percentage of interests acquired	100.00%					100.00%
Cash consideration						$ 14,100
Total purchase price	$ 15,867
Metallarte S.r.l. \| Customer Relationships
Business Acquisition [Line Items]
Acquired intangible assets useful life						15 years
Taylor Made
Business Acquisition [Line Items]
Percentage of interests acquired					100.00%
Cash consideration					$ 88,445
Taylor Made \| Customer Relationships
Business Acquisition [Line Items]
Acquired intangible assets useful life					15 years
Lexington
Business Acquisition [Line Items]
Cash consideration							$ 40,062
Total purchase price							$ 40,100
Lexington \| Customer Relationships
Business Acquisition [Line Items]
Acquired intangible assets useful life							15 years
SessaKlein S.p.A.
Business Acquisition [Line Items]
Percentage of interests acquired								100.00%
Total purchase price		$ 10,340						$ 6,500