Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Revenues	$ 1,091,553	$ 1,197,509	$ 1,311,917
Cost of revenues	999,617	1,116,506	1,185,926
Gross profit	91,936	81,003	125,991
Selling, general and administrative expenses	84,417	76,144	85,109
Goodwill and other intangible asset impairment	17,998	0	0
Operating income (loss)	(10,479)	4,859	40,882
Other income (expense):
Interest expense	(2,600)	(2,211)	(852)
Interest income	381	132	190
Other	550	(334)	(567)
Income (loss) before income tax expense	(12,148)	2,446	39,653
Provision (benefit) for federal, state and foreign income taxes	(668)	2,308	14,116
Net income (loss)	(11,480)	138	25,537
Less: Net income (loss) attributable to noncontrolling interest	0	321	(3,326)
Net income (loss) attributable to Matrix Service Company	$ (11,480)	$ (183)	$ 28,863
Basic earnings (loss) per common share (in dollars per share)	$ (0.43)	$ (0.01)	$ 1.09
Diluted earnings (loss) per common share (in dollars per share)	$ (0.43)	$ (0.01)	$ 1.07
Weighted average common shares outstanding:
Basic (in shares)	26,769	26,533	26,597
Diluted (in shares)	26,769	26,533	27,100