Note 9 - Segment Reporting (Detail) - Financial Information by Segment (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenues:
Revenues	$ 224,985	$ 230,192	$ 435,572	$ 429,374
Gross profit (loss):
Gross profit (loss)	45,840	59,199	87,014	107,880
Operating income (loss):
Operating income (loss)	7,840	22,747	13,329	35,254
Energy And Mining [Member]
Revenues:
Revenues	100,400	96,734	195,857	174,089
Gross profit (loss):
Gross profit (loss)	24,823	27,752	47,914	48,862
Operating income (loss):
Operating income (loss)	6,987	11,356	13,377	17,085
North American Sewer Rehabilitation [Member]
Revenues:
Revenues	87,430	99,590	167,235	188,704
Gross profit (loss):
Gross profit (loss)	13,650	23,180	24,948	44,258
Operating income (loss):
Operating income (loss)	627	9,847	(612)	17,354
European Sewer Rehabilitation [Member]
Revenues:
Revenues	23,609	18,003	44,306	35,633
Gross profit (loss):
Gross profit (loss)	6,107	4,972	10,624	9,250
Operating income (loss):
Operating income (loss)	1,772	1,268	2,409	1,232
Asia Pacific Sewer Rehabilitation [Member]
Revenues:
Revenues	10,735	13,750	22,946	23,623
Gross profit (loss):
Gross profit (loss)	1,536	3,137	3,889	4,692
Operating income (loss):
Operating income (loss)	(649)	594	(480)	(230)
Water Rehabilitation [Member]
Revenues:
Revenues	2,811	2,115	5,228	7,325
Gross profit (loss):
Gross profit (loss)	(276)	158	(361)	818
Operating income (loss):
Operating income (loss)	$ (897)	$ (318)	$ (1,365)	$ (187)