Earnings Per Share - Computation of earnings per share and weighted average number of basic and diluted shares (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share [Abstract]
Net income attributable to CACI	$ 30,828	$ 38,367	$ 98,782	$ 113,751
Weighted average number of basic shares outstanding during the period	23,473	23,021	23,406	22,968
Dilutive effect of SSARs/stock options and RSUs/restricted shares after application of treasury stock method	419	683	449	771
Dilutive effect of the Notes and Warrants	2,081	2	1,513	1
Weighted average number of diluted shares outstanding during the period	25,973	23,706	25,368	23,740
Basic earnings per share (in dollars per share)	$ 1.31	$ 1.67	$ 4.22	$ 4.95
Diluted earnings per share (in dollars per share)	$ 1.19	$ 1.62	$ 3.89	$ 4.79