Goodwill and Other Intangible Assets (2018 Acquisitions) (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2018	Sep. 30, 2018
2018 Power Generation and Industrial Acquisition A [Member]
Business Combinations [Line Items]
Business combinations, percentage of interests acquired		100.00%
Business combinations, description of acquired entity		a construction management firm specializing in steel building systems
2018 Power Generation and Industrial Acquisition B [Member]
Business Combinations [Line Items]
Business combinations, description of acquired entity		a wind turbine services company
2018 Acquisitions [Member]
Business Combinations [Line Items]
Business combinations, cash paid (in dollars)	$ 6.8
Contingent consideration, earn-out liabilities		$ 0.8

With respect to a business combination completed during the period, this element provides a description of the business, other than the name, which may include the industry, size, products and other important information.

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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

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

+ References

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

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-Name Accounting Standards Codification
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- Definition

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

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