Represents information about average share price determination period.

No definition available.

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- Definition

Cumulative shares purchased under Employee Stock Purchase Plan.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Cumulative weighted-average price per share.

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of fair market value.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based payment award outstanding number.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based payment award restricted stock issued in lieu of percentage of annual bonus.

+ References

No definition available.

+ Details

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- Definition

Share based compensation number of share authorized to be purchased by eligible employee

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=109197908&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 total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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://fasb.org/us-gaap/role/ref/legacyRef
-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=109197908&loc=d3e5070-113901

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-URI http://asc.fasb.org/extlink&oid=109197908&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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-Paragraph 1
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Period Type:	instant

- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

+ References

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Details

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- Details

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- Details

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Data Type:	na
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Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
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- Details

Name:	us-gaap_AwardTypeAxis=caci_StockSettledStockAppreciationRightsAndStockOptionsMember
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STOCK PLANS AND STOCK-BASED COMPENSATION (Detail Textual 1) - USD ($)	12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Income tax benefit realized	$ 7,769,000	$ 7,498,000	$ 6,476,000
ESPP Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for grants	1,250,000
Percentage of fair market value	95.00%
Maximum number of shares that an eligible employee can purchase	The maximum number of shares that an eligible employee can purchase during any quarter is equal to two times an amount determined as follows: 20 percent of such employee’s compensation over the quarter, divided by 95 percent of the fair market value of a share of common stock on the last day of the quarter.
Cumulative shares purchased under ESPP Plan	1,149,324
Cumulative weighted-average purchase price per share	$ 54.14
Shares purchased under ESPP Plan	36,629
Weighted-average price per share	$ 129.83
MSPP Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for grants	500,000
Percentage of annual bonus in lieu of which RSU received	85.00%	85.00%	85.00%
MSPP Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of annual bonus in lieu of which RSU received	100.00%
DSPP Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for grants	75,000
Percentage of annual bonus in lieu of which RSU received	100.00%
Number of awards outstanding	0
PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period to establish average share price for performance measurement	90 days
Share price	$ 127.02
Risk free rate of return	1.53%
Expected volatility	26.94%
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value of RSUs granted	$ 146.27	$ 104.45	$ 80.72
Vesting period (in years)	3 years
Total intrinsic value of RSUs that vested	$ 55,200,000	$ 26,600,000	$ 18,400,000
Income tax benefit realized	13,300,000	$ 4,800,000	$ 3,300,000
Unrecognized compensation cost	$ 37,300,000
Weighted-average period to recognize unrecognized compensation cost (in years)	2 years 8 months 12 days
SSARs and Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 0
Number of shares granted	0	0	0