Recently Issued Accounting Pronouncements (Impact Of Recently Issued Accounting Pronouncements On The Company's Statement Of Operations) (Details) (USD $) In Thousands, except Per Share data	3 Months Ended								12 Months Ended
	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2009	Sep. 30, 2009	Jun. 30, 2011		Jun. 30, 2010		Jun. 30, 2009
Interest expense and other									$ (23,144)		$ (26,353)		$ (31,125)	[1]
Income before income taxes									228,257		168,429		152,989	[1]
Income taxes									83,105		61,171		62,572	[1]
Net income before noncontrolling interest in earnings of joint venture									145,152		107,258		90,417	[1]
Noncontrolling interest in earnings of joint venture									(934)	[2]	(743)	[2]	(719)	[1],[2]
Net income attributable to CACI	45,901	36,427	33,235	28,655	29,900	26,708	26,052	23,855	144,218	[2]	106,515	[2]	89,698	[1],[2]
Basic earnings per share	$ 1.52	$ 1.20	$ 1.10	$ 0.95	$ 0.99	$ 0.89	$ 0.87	$ 0.79	$ 4.76		$ 3.53		$ 2.99	[1]
Diluted earnings per share	$ 1.44	$ 1.16	$ 1.08	$ 0.92	$ 0.96	$ 0.87	$ 0.85	$ 0.78	$ 4.61		$ 3.47		$ 2.95	[1]
Weighted-average basic shares outstanding	30,162	30,373	30,288	30,304	30,241	30,171	30,109	30,034	30,281		30,138		29,976	[1]
Weighted-average diluted shares outstanding	31,895	31,300	30,906	31,102	31,022	30,641	30,580	30,464	31,300		30,676		30,427	[1]
As Previously Reported [Member]
Interest expense and other													23,062
Income before income taxes													161,791
Income taxes													66,311
Net income before noncontrolling interest in earnings of joint venture													95,480
Basic earnings per share													$ 3.19
Diluted earnings per share													$ 3.14
Weighted-average basic shares outstanding													29,976
Weighted-average diluted shares outstanding													30,427
As Adjusted [Member]
Interest expense and other													31,864
Income before income taxes													152,989
Income taxes													62,572
Net income before noncontrolling interest in earnings of joint venture													90,417
Noncontrolling interest in earnings of joint venture													(719)
Net income attributable to CACI													89,698
Basic earnings per share													$ 2.99
Diluted earnings per share													$ 2.95
Weighted-average basic shares outstanding													29,976
Weighted-average diluted shares outstanding													30,427
ASC 470-20 [Member]
Interest expense and other													9,521
Income before income taxes													(9,521)
Income taxes													(3,739)
Net income before noncontrolling interest in earnings of joint venture													(5,782)
Net income attributable to CACI													(5,782)
Basic earnings per share													$ (0.20)
Diluted earnings per share													$ (0.19)
ASC 810 [Member]
Interest expense and other													(719)
Income before income taxes													719
Net income before noncontrolling interest in earnings of joint venture													719
Noncontrolling interest in earnings of joint venture													$ (719)

[1] Certain amounts for the year ended June 30, 2009 have been adjusted to reflect the retroactive application of new accounting standards. See Note 3.

[2] Certain amounts as of and for the years ended June 30, 2008 and 2009 have been adjusted to reflect the retroactive application of new accounting standards. See Note 3.