Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income		$ 7,198	$ 12,178	$ 5,722	$ 19,931
Other comprehensive income (loss):
Currency translation adjustments		(6,510)	12,569	(4,282)	16,438
Deferred gain (loss) on hedging activity, net of tax	[1]	684	(307)	1,178	176
Pension activity, net of tax	[2]	12	(11)	5	(16)
Total comprehensive income		1,384	24,429	2,623	36,529
Comprehensive (income) loss attributable to non-controlling interests		1,023	(1,111)	377	(2,980)
Comprehensive income attributable to Aegion Corporation		$ 2,407	$ 23,318	$ 3,000	$ 33,549

[1] Amounts presented net of tax of $245 and $(204) for the quarters ended June 30, 2018 and 2017, respectively, and $422 and $117 for the six months ended June 30, 2018 and 2017, respectively.

[2] Amounts presented net of tax of $3 and $(3) for the quarters ended June 30, 2018 and 2017, respectively, and $1 and $(4) for the six months ended June 30, 2018 and 2017, respectively.