Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Revenues	$ 335,030	$ 354,473	$ 659,891	$ 679,648
Cost of revenues	263,977	274,705	527,334	532,468
Gross profit	71,053	79,768	132,557	147,180
Operating expenses	54,222	58,109	110,364	110,855
Acquisition and divestiture expenses	832	0	1,224	533
Restructuring and related charges	1,540	0	3,329	0
Operating income	14,459	21,659	17,640	35,792
Other income (expense):
Interest expense	(3,923)	(4,005)	(9,366)	(8,052)
Interest income	62	35	109	84
Other	(506)	(408)	(768)	(795)
Total other expense	(4,367)	(4,378)	(10,025)	(8,763)
Income before taxes on income	10,092	17,281	7,615	27,029
Taxes on income	2,894	5,103	1,893	7,098
Net income	7,198	12,178	5,722	19,931
Non-controlling interests (income) loss	723	(1,078)	130	(2,960)
Net income attributable to Aegion Corporation	$ 7,921	$ 11,100	$ 5,852	$ 16,971
Earnings per share attributable to Aegion Corporation:
Net income (loss) per share, basic (in dollars per share)	$ 0.24	$ 0.33	$ 0.18	$ 0.51
Net income (loss) per share, diluted (in dollars per share)	$ 0.24	$ 0.33	$ 0.18	$ 0.50