Business Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from external customers	$ 894,186	$ 931,627	$ 1,758,451	$ 1,862,863
Net income attributable to CACI	34,962	39,676	67,954	75,384
Reportable Geographical Components | Domestic
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from external customers	857,457	897,346	1,688,332	1,795,630
Net income attributable to CACI	32,234	37,010	62,914	70,417
Reportable Geographical Components | International
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from external customers	36,729	34,281	70,119	67,233
Net income attributable to CACI	$ 2,728	$ 2,666	$ 5,040	$ 4,967