Document and Entity Information - shares	6 Months Ended
	Dec. 31, 2017	Feb. 05, 2018
Document Documentand Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q2
Trading Symbol	MTRX
Entity Registrant Name	MATRIX SERVICE CO
Entity Central Index Key	0000866273
Current Fiscal Year End Date	--06-30
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		26,817,064