Business Segment Information (Summarized Financial Information Of Reportable Segments) (Details) (USD $) In Thousands	3 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from external customers	$ 924,395	$ 833,971
Net income attributable to CACI	42,140	28,655
Domestic Operations [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from external customers	896,721	805,735
Net income attributable to CACI	40,395	27,105
International Operations [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from external customers	27,674	28,236
Net income attributable to CACI	$ 1,745	$ 1,550