Document And Entity Information - USD ($)	12 Months Ended
	Jun. 30, 2018	Aug. 07, 2018	Dec. 31, 2017
Document And Entity Information [Abstract]
Entity Registrant Name	CACI INTERNATIONAL INC /DE/
Entity Central Index Key	0000016058
Trading Symbol	caci
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Current Fiscal Year End Date	--06-30
Entity Filer Category	Large Accelerated Filer
Entity Well-known Seasoned Issuer	Yes
Entity Common Stock, Shares Outstanding		24,705,478
Entity Public Float			$ 3,198,962,896
Document Type	10-K
Document Period End Date	Jun. 30, 2018
Amendment Flag	false
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY