Goodwill and Intangible Assets (Details 3) (USD $) In Thousands	9 Months Ended			9 Months Ended
Sep. 24, 2011	Sep. 24, 2011 Engineered Infrastructure Products segment	Sep. 24, 2011 Utility Support Structures segment	Dec. 25, 2010 Utility Support Structures segment	Sep. 24, 2011 Coatings segment	Sep. 24, 2011 Irrigation segment	Sep. 24, 2011 Other
Carrying amount of goodwill
Balance at the beginning of the period	$ 314,847	$ 152,062	$ 77,141	$ 77,141	$ 64,868	$ 2,064	$ 18,712
Acquisition	939					939
Foreign currency translation	(646)	(478)			129	(155)	(142)
Balance at the end of the period	$ 315,140	$ 151,584	$ 77,141	$ 77,141	$ 64,997	$ 2,848	$ 18,570

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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