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The amount of identifiable intangible assets recognized as of the acquisition date.

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Acquisitions (Allocation of Purchase Price) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 30, 2014	Oct. 29, 2014	Jul. 07, 2014	Nov. 07, 2013
Business Acquisition [Line Items]
Goodwill	$ 82,949us-gaap_Goodwill	$ 57,781us-gaap_Goodwill	$ 41,237us-gaap_Goodwill
Chemtec [Member]
Business Acquisition [Line Items]
Current assets				15,528
Other assets				0
Property, plant and equipment				4,705
Goodwill				22,302
Other intangibles				33,130
Current liabilities				(6,756)
Total				68,909
FWO [Member]
Business Acquisition [Line Items]
Current assets					131
Other assets					0
Property, plant and equipment					0
Goodwill					971
Other intangibles					419
Current liabilities					(418)
Total					1,103
L.B. Foster Ball Winch, Inc. [Member]
Business Acquisition [Line Items]
Current assets						3,180	1,857
Other assets						45	64
Property, plant and equipment						7,648	5,555
Goodwill						1,936	16,544
Other intangibles						1,348	14,682
Current liabilities						(1,677)	(707)
Total						$ 12,480	$ 37,995