Stock-Based Compensation (Detail Textual) $ in Millions	9 Months Ended
Mar. 31, 2018 USD ($) shares
PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period to establish average share price for performance measurement	90 days
PRSUs \| September 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSUs granted	180,570
Additional PRSUs earned pursuant to condition	63,642
PRSUs \| September 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSUs granted	208,160
Additional PRSUs earned pursuant to condition	48,068
PRSUs \| September 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSUs granted	193,420
Additional PRSUs earned pursuant to condition	21,824
PRSUs \| September 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSUs granted	146,550
Potential additional PRSUs to be earned pursuant to condition	146,550
Percentage of earned award vesting after three years	50.00%
Percentage of earned award vesting after four years	50.00%
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSUs granted	269,898
Unrecognized compensation cost \| $	$ 43.0
Weighted-average period to recognize unrecognized compensation cost (in years)	2 years 10 months 24 days
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, expiration period	10 years
2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for grants	1,200,000
Cumulative equity instruments awarded	311,654
Cumulative equity instruments forfeited	96,259

Represents the number of additional PRSUs earned pursuant to condition.

No definition available.

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- Definition

Represents information about average share price determination period.

+ References

No definition available.

+ Details

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- Definition

Cumulative equity instruments awarded.

+ References

No definition available.

+ Details

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Namespace Prefix:	caci_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Cumulative equity instruments forfeited.

+ References

No definition available.

+ Details

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- Definition

Service vesting condition which stipulates that 50 percent of the earned award will vest after four years.

+ References

No definition available.

+ Details

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- Definition

Service vesting condition which stipulates that 50 percent of the earned award will vest after three years.

+ References

No definition available.

+ Details

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- Definition

Represents the number of potential additional PRSUs to be earned pursuant to condition.

+ References

No definition available.

+ Details

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Namespace Prefix:	caci_
Data Type:	xbrli:sharesItemType
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- Definition

Period in which equity awards can be granted under stock incentive plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	caci_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Details

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- Details

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