CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Total CACI Shareholders' Equity	Noncontrolling Interest
Beginning balance at Jun. 30, 2020	$ 2,661,310	$ 4,253	$ 573,744	$ 2,731,644	$ (72,285)	$ (576,181)	$ 2,661,175	$ 135
Beginning balance, shares at Jun. 30, 2020		42,525				17,432
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	320,466			320,466			320,466
Stock-based compensation expense	23,841		23,841				23,841
Tax withholdings on restricted share vestings	(19,486)	$ 14	(19,500)				(19,486)
Tax withholdings on restricted share vestings (in shares)		147
Other comprehensive (loss) income, net of tax	33,309				33,309		33,309
Repurchases of common stock	(506,629)		(100,065)			$ (406,564)	(506,629)
Repurchases of common stock (in shares)						(1,721)
Treasury stock issued under stock purchase plans	6,583		19			$ 6,564	6,583
Treasury stock issued under stock purchase plans (in shares)						(31)
Ending balance at Mar. 31, 2021	2,519,394	$ 4,267	478,039	3,052,110	(38,976)	$ (976,181)	2,519,259	135
Ending balance, shares at Mar. 31, 2021		42,672				19,122
Beginning balance at Dec. 31, 2020	2,884,279	$ 4,266	570,176	2,931,766	(45,883)	$ (576,181)	2,884,144	135
Beginning balance, shares at Dec. 31, 2020		42,663				17,432
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	120,344			120,344			120,344
Stock-based compensation expense	8,800		8,800				8,800
Tax withholdings on restricted share vestings	(904)	$ 1	(905)				(904)
Tax withholdings on restricted share vestings (in shares)		9
Other comprehensive (loss) income, net of tax	6,907				6,907		6,907
Repurchases of common stock	(502,209)		(100,032)			$ (402,177)	(502,209)
Repurchases of common stock (in shares)						(1,699)
Treasury stock issued under stock purchase plans	2,177					$ 2,177	2,177
Treasury stock issued under stock purchase plans (in shares)						(9)
Ending balance at Mar. 31, 2021	2,519,394	$ 4,267	478,039	3,052,110	(38,976)	$ (976,181)	2,519,259	135
Ending balance, shares at Mar. 31, 2021		42,672				19,122
Beginning balance at Jun. 30, 2021	2,665,278	$ 4,268	484,260	3,189,087	(36,291)	$ (976,181)	2,665,143	135
Beginning balance, shares at Jun. 30, 2021		42,676				19,122
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	273,825			273,825			273,825
Stock-based compensation expense	23,085		23,085				23,085
Tax withholdings on restricted share vestings	(14,571)	$ 14	(14,585)				(14,571)
Tax withholdings on restricted share vestings (in shares)		141
Other comprehensive (loss) income, net of tax	13,725				13,725		13,725
Repurchases of common stock	(7,301)		70,631			$ (77,932)	(7,301)
Repurchases of common stock (in shares)						(310)
Treasury stock issued under stock purchase plans	6,845		61			$ 6,784	6,845
Treasury stock issued under stock purchase plans (in shares)						(28)
Ending balance at Mar. 31, 2022	2,960,886	$ 4,282	563,452	3,462,912	(22,566)	$ (1,047,329)	2,960,751	135
Ending balance, shares at Mar. 31, 2022		42,817				19,404
Beginning balance at Dec. 31, 2021	2,845,710	$ 4,281	555,968	3,367,495	(34,840)	$ (1,047,329)	2,845,575	135
Beginning balance, shares at Dec. 31, 2021		42,810				19,404
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	95,417			95,417			95,417
Stock-based compensation expense	8,387		8,387				8,387
Tax withholdings on restricted share vestings	(772)	$ 1	(773)				(772)
Tax withholdings on restricted share vestings (in shares)		7
Other comprehensive (loss) income, net of tax	12,274				12,274		12,274
Repurchases of common stock	(2,306)		(130)			$ (2,176)	(2,306)
Repurchases of common stock (in shares)						(9)
Treasury stock issued under stock purchase plans	2,176					$ 2,176	2,176
Treasury stock issued under stock purchase plans (in shares)						(9)
Ending balance at Mar. 31, 2022	$ 2,960,886	$ 4,282	$ 563,452	$ 3,462,912	$ (22,566)	$ (1,047,329)	$ 2,960,751	$ 135
Ending balance, shares at Mar. 31, 2022		42,817				19,404