Note 4 - Goodwill and Intangible Assets (Details) - Reconciliation Goodwill (USD $)	6 Months Ended
	Jun. 30, 2013		Apr. 30, 2012
Goodwill [Line Items]
Goodwill	$ 272,294,000		$ 20,008,000
Additions to goodwill through acquisitions	200,000
Foreign currency translation	(2,000,000)
Goodwill	270,525,000	[1]	20,008,000
Energy And Mining [Member]
Goodwill [Line Items]
Goodwill	76,700,000	[2]
Additions to goodwill through acquisitions		[2]
Foreign currency translation	(600,000)	[2]
Goodwill	76,100,000	[1],[2]
North American Water and Wastewater [Member]
Goodwill [Line Items]
Goodwill	101,900,000
Foreign currency translation	800,000
Goodwill	102,700,000	[1]
International Water and Wastewater [Member]
Goodwill [Line Items]
Goodwill	28,100,000
Foreign currency translation	(1,900,000)
Goodwill	26,200,000	[1]
Commercial And Structural [Member]
Goodwill [Line Items]
Goodwill	65,600,000	[3]
Additions to goodwill through acquisitions	200,000	[3]
Foreign currency translation	(300,000)	[3]
Goodwill	$ 65,500,000	[1]

[1] The Company does not have any accumulated impairment charges.

[2] During the second quarter of 2013, the Company approved a plan of liquidation of and, in connection therewith, recorded a write-down of the $1.4 million of goodwill associated with BWW, which operation now is reported as discontinued. Consequently, the goodwill associated with BWW is no longer included in this table. Additionally, all prior year balances have been restated. For further information, see Note 9 contained within this report.

[3] During 2013, the Company recorded an increase of goodwill of $0.2 million related to the Fyfe Asia acquisition.