Document And Entity Information - shares	6 Months Ended
Document And Entity Information - shares	Dec. 31, 2016	Jan. 31, 2017
Document And Entity Information [Abstract]
Entity Registrant Name	CACI INTERNATIONAL INC /DE/
Entity Central Index Key	0000016058
Trading Symbol	caci
Current Fiscal Year End Date	--06-30
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		24,393,563
Document Type	10-Q
Document Period End Date	Dec. 31, 2016
Amendment Flag	false
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q2

CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Revenue	$ 1,057,530	$ 830,437	$ 2,130,810	$ 1,652,879
Costs of revenue:
Direct costs	705,321	547,140	1,433,542	1,084,564
Indirect costs and selling expenses	253,822	213,144	511,160	418,844
Depreciation and amortization	18,132	14,670	36,195	29,481
Total costs of revenue	977,275	774,954	1,980,897	1,532,889
Income from operations	80,255	55,483	149,913	119,990
Interest expense and other, net	12,325	8,180	24,814	17,362
Income before income taxes	67,930	47,303	125,099	102,628
Income taxes	25,510	16,851	46,016	37,544
Net income	$ 42,420	$ 30,452	$ 79,083	$ 65,084
Basic earnings per share	$ 1.74	$ 1.26	$ 3.25	$ 2.69
Diluted earnings per share	$ 1.69	$ 1.23	$ 3.16	$ 2.63
Weighted-average basic shares outstanding	24,387	24,246	24,363	24,227
Weighted-average diluted shares outstanding	25,069	24,786	24,998	24,754

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 42,420	$ 30,452	$ 79,083	$ 65,084
Other comprehensive (loss) income:
Foreign currency translation adjustment	(6,424)	(3,337)	(10,126)	(7,747)
Change in fair value of interest rate swap agreements, net of tax	10,045	3,832	12,899	798
Other comprehensive (loss) income, net of tax	3,621	495	2,773	(6,949)
Comprehensive income	$ 46,041	$ 30,947	$ 81,856	$ 58,135

CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Dec. 31, 2016	Jun. 30, 2016
Current assets:
Cash and cash equivalents	$ 72,650	$ 49,082
Accounts receivable, net	717,721	803,817
Prepaid expenses and other current assets	69,679	68,939
Total current assets	860,050	921,838
Goodwill	2,571,297	2,585,343
Intangible assets, net	254,481	275,372
Property and equipment, net	86,406	81,362
Supplemental retirement savings plan assets	88,721	89,937
Accounts receivable, long-term	7,393	8,330
Other long-term assets	28,817	25,159
Total assets	3,897,165	3,987,341
Current liabilities:
Current portion of long-term debt	67,456	53,965
Accounts payable	39,293	95,270
Accrued compensation and benefits	212,480	228,362
Other accrued expenses and current liabilities	179,705	187,579
Total current liabilities	498,934	565,176
Long-term debt, net of current portion	1,292,348	1,402,079
Supplemental retirement savings plan obligations, net of current portion	80,685	76,995
Deferred income taxes	261,956	248,458
Other long-term liabilities	67,283	87,320
Total liabilities	2,201,206	2,380,028
COMMITMENTS AND CONTINGENCIES
Shareholders’ equity:
Preferred stock $0.10 par value, 10,000 shares authorized, no shares issued
Common stock $0.10 par value, 80,000 shares authorized; 41,828 shares issued and 24,393 outstanding at December 31, 2016 and 41,758 shares issued and 24,323 outstanding at June 30, 2016	4,183	4,176
Additional paid-in capital	565,106	558,324
Retained earnings	1,741,031	1,661,948
Accumulated other comprehensive loss	(38,310)	(41,083)
Treasury stock, at cost (17,435 and 17,435 shares, respectively)	(576,186)	(576,187)
Total CACI shareholders’ equity	1,695,824	1,607,178
Noncontrolling interest	135	135
Total shareholders’ equity	1,695,959	1,607,313
Total liabilities and shareholders’ equity	$ 3,897,165	$ 3,987,341

CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parentheticals) - $ / shares	Dec. 31, 2016	Jun. 30, 2016
Statement Of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.10	$ 0.10
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized	80,000,000	80,000,000
Common stock, shares issued	41,828,000	41,758,000
Common stock, shares outstanding	24,393,000	24,323,000
Treasury stock, shares at cost	17,435,000	17,435,000

CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 79,083	$ 65,084
Reconciliation of net income to net cash provided by operating activities:
Depreciation and amortization	36,195	29,481
Amortization of deferred financing costs	2,252	1,152
Loss on disposal of fixed assets	975
Stock-based compensation expense	10,557	8,473
Deferred income tax expense	5,081	12,045
Equity in earnings of unconsolidated ventures	(103)	(98)
Changes in operating assets and liabilities, net of effect of business acquisitions:
Accounts receivable, net	71,080	35,216
Prepaid expenses and other assets	1,649	(7,170)
Accounts payable and other accrued expenses	(58,873)	11,870
Accrued compensation and benefits	(15,339)	(16,998)
Income taxes payable and receivable	(391)	(2,768)
Supplemental retirement savings plan obligations and other long-term liabilities	3,184	(647)
Net cash provided by operating activities	135,350	135,640
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(21,826)	(7,642)
Cash paid for business acquisitions, net of cash acquired	(5,605)	(15,578)
Proceeds from net working capital refund of acquired business	13,619
Proceeds from equity method investments	4,681
Other	1,051	(684)
Net cash used in investing activities	(8,080)	(23,904)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from borrowings under bank credit facilities	240,500	154,488
Principal payments made under bank credit facilities	(338,991)	(228,982)
Proceeds from employee stock purchase plans	2,262	1,577
Repurchases of common stock	(2,243)	(1,689)
Payment of taxes for equity transactions	(3,632)	(2,560)
Other		451
Net cash used in financing activities	(102,104)	(76,715)
Effect of exchange rate changes on cash and cash equivalents	(1,598)	(1,388)
Net increase in cash and cash equivalents	23,568	33,633
Cash and cash equivalents, beginning of period	49,082	35,364
Cash and cash equivalents, end of year	72,650	68,997
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Cash paid during the period for income taxes, net of refunds	41,273	28,237
Cash paid during the period for interest	22,512	16,362
Non-cash financing and investing activities:
Accrued capital expenditures	$ 1,482	$ 266

Basis of Presentation

6 Months Ended

Dec. 31, 2016

Organization Consolidation And Presentation Of Financial Statements Abstract

Basis of Presentation

1.	Basis of Presentation

The accompanying unaudited consolidated financial statements of CACI International Inc and subsidiaries (CACI or the Company) have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (SEC) and include the assets, liabilities, results of operations, comprehensive income and cash flows for the Company, including its subsidiaries and ventures that are majority-owned or otherwise controlled by the Company. Certain information and note disclosures normally included in the annual financial statements prepared in accordance with U.S. generally accepted accounting principles (GAAP) have been condensed or omitted pursuant to those rules and regulations, although the Company believes that the disclosures made are adequate to make the information presented not misleading. All intercompany balances and transactions have been eliminated in consolidation.

The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable and amounts included in other current assets and current liabilities that meet the definition of a financial instrument approximate fair value because of the short-term nature of these amounts. The fair value of the Company’s debt outstanding as of December 31, 2016 under its bank credit facility approximates its carrying value. The fair value of the Company’s debt under its bank credit facility was estimated using Level 2 inputs based on market data of companies with a corporate rating similar to CACI’s that have recently priced credit facilities. See Notes 6 and 12.

In the opinion of management, the accompanying unaudited consolidated financial statements reflect all adjustments and reclassifications (all of which are of a normal, recurring nature) that are necessary for the fair presentation of the periods presented. It is suggested that these unaudited consolidated financial statements be read in conjunction with the audited consolidated financial statements and the notes thereto included in the Company’s latest annual report to the SEC on Form 10-K for the year ended June 30, 2016. The results of operations for the three and six months ended December 31, 2016 are not necessarily indicative of the results to be expected for any subsequent interim period or for the full fiscal year.

Recent Accounting Pronouncements

6 Months Ended

Dec. 31, 2016

New Accounting Pronouncements And Changes In Accounting Principles [Abstract]

Recent Accounting Pronouncements

2.	Recent Accounting Pronouncements

In January 2017, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2017-01, Clarifying the Definition of a Business, which revises the definition of a business and provides guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The guidance is effective for the fiscal year, and interim periods within that fiscal year, beginning after December 15, 2017. The Company is currently evaluating the impact of the adoption of this standard on its consolidated financial statements.

In March 2016, the FASB issued ASU No. 2016-09, Improvements to Employee Share-Based Payment Accounting, which simplifies several aspects of the accounting for share-based payments, including income tax consequences and classification on the statement of cash flows. Under the new standard, all excess tax benefits and tax deficiencies will be recognized as income tax expense or benefit in the income statement as discrete items in the reporting period in which they occur. Additionally, excess tax benefits will be classified as an operating activity on the statement of cash flows. In regards to forfeitures, the entity can make an accounting policy election to either recognize forfeitures as they occur or estimate the number of awards expected to be forfeited. The guidance in ASU 2016-09 is effective for the fiscal year, and interim periods within that fiscal year, beginning after December 15, 2016. Early adoption is permitted in any interim or annual period, with adjustments reflected as of the beginning of the fiscal year of adoption. The Company early adopted this standard during the fourth quarter of FY16, and therefore reported the impact as though the ASU had been adopted on July 1, 2015.

Upon adoption, the Company recognized excess tax benefits of $0.1 million and $0.9 million during the three and six months ended December 31, 2015 as a reduction to tax expense in the Consolidated Statements of Operations, as though ASU 2016-09 had been in effect since the beginning of FY16. Consequently, this resulted in an increase in net income, an increase in earnings per share and a decrease in the annual effective tax rate. In addition, the excess tax benefits that were previously presented as a financing activity on the Consolidated Statements of Cash Flows are now presented as an operating activity, with periods prior to FY16 retrospectively adjusted. With respect to forfeitures, the Company will continue to estimate the number of awards expected to be forfeited in accordance with our existing accounting policy.

In February 2016, the FASB issued ASU No. 2016-02, Leases, which amends the existing guidance on accounting for leases. The new standard requires lessees to put virtually all leases on the balance sheet by recognizing lease assets and lease liabilities. Lessor accounting is largely unchanged from that applied under previous guidance. The amended guidance is effective for the fiscal year, and interim periods within that fiscal year, beginning after December 15, 2018, and requires a modified retrospective approach. Early adoption is permitted. The Company is currently evaluating the impact of the adoption of this standard on its consolidated financial statements.

In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which supersedes nearly all existing revenue recognition guidance under U.S. GAAP. The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration to which an entity expects to be entitled for those goods or services. ASU 2014-09 defines a five step process to achieve this core principle and, in doing so, more judgment and estimates may be required within the revenue recognition process than are required under existing U.S. GAAP. On July 9, 2015, the FASB approved a one-year deferral of the effective date of ASU 2014-09 to annual reporting periods, including interim reporting periods within those periods, beginning after December 15, 2017, using either a full retrospective approach or a modified approach. Early adoption up to the original effective date is permitted. The Company is currently evaluating the impact of the adoption of this standard on its consolidated financial statements and has not yet determined the method by which the Company will adopt the standard.

- Definition

The entire disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

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+ Details

Acquisitions

6 Months Ended

Dec. 31, 2016

Business Combinations [Abstract]

Acquisitions

3.	Acquisitions

NSS Acquisition

On February 1, 2016, the Company acquired 100 percent of the outstanding shares of L-3 National Security Solutions, Inc. and L-3 Data Tactics Corporation (together, “NSS”). NSS is a prime mission partner to the U.S. Department of Defense (DoD), U.S. government intelligence agencies, and U.S. federal civilian agencies. The acquisition will expand CACI’s opportunities in many of our key market areas and expand our current customer base. CACI financed the acquisition by borrowing $250.0 million under its existing revolving facility and by entering into an eighth amendment and first incremental facility amendment to its credit facility to allow for the incurrence of $300.0 million in additional term loans.

The initial purchase consideration paid at closing to acquire NSS was $550.0 million plus $11.2 million representing a preliminary net working capital adjustment. Subsequent to closing, CACI received a refund of $13.6 million for the final net working capital adjustment and is expecting an additional $5.7 million refund for tax-related adjustments.

CACI is in the process of finalizing its valuation of all the assets acquired and liabilities assumed. As the amounts recorded for certain assets and liabilities are preliminary in nature, they are subject to adjustment as additional information is obtained about the facts and circumstances that existed at the acquisition date. The final determination of fair values of certain assets and liabilities will be completed within the measurement period of up to one year from the acquisition date as permitted under GAAP. The NSS acquisition could necessitate the need to use the full one year measurement period to adequately analyze and assess a number of factors used in establishing the asset and liability fair values as of the acquisition date, including receivables and deferred revenue, contractual obligations, income tax obligations, and certain reserves. Any potential adjustments made could be material in relation to the preliminary values presented in the table below.

During the six months ended December 31, 2016 we continued to obtain information to refine estimated fair values. As a result of the additional information, the Company recorded measurement period adjustments that increased other current assets, receivables and other accrued expenses by $2.6 million, $1.2 million and $0.6 million, respectively, reduced the purchase consideration by $5.5 million and reduced goodwill by $8.6 million.

Based on the Company’s preliminary valuation, the total estimated consideration of $541.9 million has been allocated to assets acquired and liabilities assumed as follows (in thousands):

Cash and cash equivalents	$	2,596
Accounts receivable		211,055
Prepaid expenses and other current assets		14,628
Property and equipment		21,320
Intangible assets		110,500
Goodwill		359,088
Other long-term assets		437
Accounts payable		(57,616	)
Accrued compensation and benefits		(38,953	)
Other accrued expenses and current liabilities		(38,116	)
Deferred income taxes		(37,796	)
Other long-term liabilities		(5,280	)
Total estimated consideration	$	541,863

The goodwill of $359.1 million is largely attributable to the assembled workforce of NSS and expected synergies between the Company and NSS. The estimated fair value attributed to intangible assets, which consists of customer contracts and related customer relationships, is being amortized on an accelerated basis over approximately 15 years. The fair value attributed to the intangible assets acquired was based on preliminary estimates, assumptions, and other information compiled by management, including independent valuations that utilized established valuation techniques. Of the value attributed to goodwill and intangible assets, $47.7 million is deductible for income tax purposes.

Other Acquisition

On October 1, 2016, CACI Limited acquired a business in the United Kingdom that provides outsourced database managed services and associated database segmentation and analytics for large corporate customers. The purchase consideration for this business is approximately $2.8 million, which includes initial cash payments, deferred consideration and contingent consideration to be paid upon achieving certain metrics.

- Definition

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

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+ Details

Intangible Assets

6 Months Ended

Dec. 31, 2016

Finite Lived Intangible Assets Net [Abstract]

Intangible Assets

4.	Intangible Assets

Intangible assets consisted of the following (in thousands):

	December 31,			June 30,
	2016			2016
Customer contracts and related customer relationships	$	635,004		$	635,826
Acquired technologies		28,436			28,074
Covenants not to compete		3,278			3,321
Other		1,535			1,551
Intangible assets		668,253			668,772
Accumulated amortization:
Customer contracts and related customer relationships		(383,327	)		(363,412	)
Acquired technologies		(26,147	)		(25,693	)
Covenants not to compete		(3,231	)		(3,245	)
Other		(1,067	)		(1,050	)
Less accumulated amortization		(413,772	)		(393,400	)
Total intangible assets, net	$	254,481		$	275,372

Intangible assets are primarily amortized on an accelerated basis over periods ranging from one to fifteen years. The weighted-average period of amortization for all customer contracts and related customer relationships as of December 31, 2016 is 14.1 years, and the weighted-average remaining period of amortization is 11.6 years. The weighted-average period of amortization for acquired technologies as of December 31, 2016 is 9.6 years, and the weighted-average remaining period of amortization is 6.1 years.

Expected amortization expense for the remainder of the fiscal year ending June 30, 2017, and for each of the fiscal years thereafter, is as follows (in thousands):

Fiscal year ending June 30,	Amount
2017 (six months)	$	19,383
2018		36,208
2019		31,551
2020		27,088
2021		23,896
Thereafter		116,355
Total intangible assets, net	$	254,481

Goodwill

6 Months Ended

Dec. 31, 2016

Goodwill [Abstract]

Goodwill

5.

Goodwill

The changes in the carrying amount of goodwill for the year ended June 30, 2016 and the six months ended December 31, 2016 are as follows (in thousands):

	Domestic			International			Total
Balance at June 30, 2015	$	2,108,768		$	81,048		$	2,189,816
Business acquisitions		378,380			29,939			408,319
Foreign currency translation		—			(12,792	)		(12,792	)
Balance at June 30, 2016		2,487,148			98,195			2,585,343
Business acquisitions		(8,635	)		2,220			(6,415	)
Foreign currency translation		—			(7,631	)		(7,631	)
Balance at December 31, 2016	$	2,478,513		$	92,784		$	2,571,297

Long-term Debt

6 Months Ended

Dec. 31, 2016

Long Term Debt [Abstract]

Long-term Debt

6.	Long-term Debt

Long-term debt consisted of the following (in thousands):

	December 31,			June 30,
	2016			2016
Bank credit facility – term loans	$	1,019,341		$	1,032,833
Bank credit facility – revolver loans		355,000			440,000
Principal amount of long-term debt		1,374,341			1,472,833
Less unamortized debt issuance costs		(14,537	)		(16,789	)
Total long-term debt		1,359,804			1,456,044
Less current portion		(67,456	)		(53,965	)
Long-term debt, net of current portion	$	1,292,348		$	1,402,079

Bank Credit Facility

The Company has a $1,981.3 million credit facility (the Credit Facility), which consists of an $850.0 million revolving credit facility (the Revolving Facility) and a $1,131.3 million term loan (the Term Loan). The Revolving Facility has subfacilities of $100.0 million for same-day swing line loan borrowings and $25.0 million for stand-by letters of credit. At any time and so long as no default has occurred, the Company has the right to increase the Revolving Facility or the Term Loan in an aggregate principal amount of up to the greater of $400.0 million or an amount subject to 2.75 times senior secured leverage, calculated assuming the Revolving Facility is fully drawn, with applicable lender approvals. The Credit Facility is available to refinance existing indebtedness and for general corporate purposes, including working capital expenses and capital expenditures.

The Credit Facility was amended during the third quarter of FY16 in connection with the Company’s acquisition of NSS (see Note 3). CACI financed the transaction by borrowing $250.0 million under its existing Revolving Facility and by entering into an eighth amendment and first incremental facility amendment to its Credit Facility to allow for the incurrence of $300.0 million in additional Term Loans.

The Revolving Facility is a secured facility that permits continuously renewable borrowings of up to $850.0 million. As of December 31, 2016, the Company had $355.0 million outstanding under the Revolving Facility, no borrowings on the swing line and an outstanding letter of credit of $0.4 million. The Company pays a quarterly facility fee for the unused portion of the Revolving Facility.

The Term Loan is a five-year secured facility under which principal payments are due in quarterly installments of $13.5 million through June 30, 2018 and $27.0 million thereafter until the balance is due in full on June 1, 2020. As of December 31, 2016, the Company had $1,019.3 million outstanding under the Term Loan.

The interest rates applicable to loans under the Credit Facility are floating interest rates that, at the Company’s option, equal a base rate or a Eurodollar rate plus, in each case, an applicable rate based upon the Company’s consolidated total leverage ratio. As of December 31, 2016, the effective interest rate, including the impact of the Company’s floating-to-fixed interest rate swap agreements and excluding the effect of amortization of debt financing costs, for the outstanding borrowings under the Credit Facility was 3.22 percent.

The Credit Facility requires the Company to comply with certain financial covenants, including a maximum senior secured leverage ratio, a maximum total leverage ratio and a minimum fixed charge coverage ratio. The Credit Facility also includes customary negative covenants restricting or limiting the Company’s ability to guarantee or incur additional indebtedness, grant liens or other security interests to third parties, make loans or investments, transfer assets, declare dividends or redeem or repurchase capital stock or make other distributions, prepay subordinated indebtedness and engage in mergers, acquisitions or other business combinations, in each case except as expressly permitted under the Credit Facility. As of December 31, 2016, the Company was in compliance with all of the financial covenants. A majority of the Company’s assets serve as collateral under the Credit Facility.

All debt issuance costs are being amortized from the date incurred to the expiration date of the Credit Facility.

Cash Flow Hedges

The Company periodically uses derivative financial instruments as part of a strategy to manage exposure to market risks associated with interest rate fluctuations. The Company has entered into several floating-to-fixed interest rate swap agreements for an aggregate notional amount of $900.0 million which hedge a portion of the Company’s floating rate indebtedness. The swaps mature at various dates through 2022. The Company has designated the swaps as cash flow hedges. Unrealized gains are recognized as assets while unrealized losses are recognized as liabilities. The interest rate swap agreements are highly correlated to the changes in interest rates to which the Company is exposed. Unrealized gains and losses on these swaps are designated as effective or ineffective. Realized gains and losses in connection with each required interest payment are reclassified from accumulated other comprehensive income or loss to interest expense. The Company does not hold or issue derivative financial instruments for trading purposes.

The effect of derivative instruments in the consolidated statements of operations and accumulated other comprehensive loss for the three and six months ended December 31, 2016 and 2015 is as follows (in thousands):

	Three Months Ended				Six Months Ended
	December 31,				December 31,
	2016		2015		2016		2015
Gain (loss) recognized in other comprehensive income	$	7,920	$	1,440	$	8,525	$	(4,016	)
Amounts reclassified to earnings from accumulated other comprehensive loss		2,125		2,392		4,374		4,814
Net current period other comprehensive income	$	10,045	$	3,832	$	12,899	$	798

The aggregate maturities of long-term debt at December 31, 2016 are as follows (in thousands):

Twelve months ending December 31,
2017	$	67,456
2018		80,947
2019		107,930
2020		1,118,008
Principal amount of long-term debt		1,374,341
Less unamortized debt issuance costs		(14,537	)
Total long-term debt	$	1,359,804

Commitments and Contingencies

6 Months Ended

Dec. 31, 2016

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

7.	Commitments and Contingencies

The Company is involved in various lawsuits, claims, and administrative proceedings arising in the normal course of business. Management is of the opinion that any liability or loss associated with such matters, either individually or in the aggregate, will not have a material adverse effect on the Company’s operations and liquidity.

Government Contracting

Payments to the Company on cost-plus-fee and time-and-materials contracts are subject to adjustment upon audit by the Defense Contract Audit Agency (DCAA) and other government agencies that do not utilize DCAA’s services. The DCAA is currently nearing completion of its audits of the Company’s incurred cost submissions for the year ended June 30, 2011 and an intelligence agency is nearing completion of its audit of direct costs on selected contracts through our fiscal year ended June 30, 2012. DCAA audits of our incurred cost submissions for the year ended June 30, 2012 have commenced, and an intelligence agency has commenced audits of direct costs on selected contracts through our fiscal year ended June 30, 2015. In the opinion of management, adjustments that may result from these audits and the audits not yet started are not expected to have a material effect on the Company’s financial position, results of operations, or cash flows as the Company has accrued its best estimate of potential disallowances. Additionally, the DCAA continually reviews the cost accounting and other practices of government contractors, including the Company. In the course of those reviews, cost accounting and other issues are identified, discussed and settled.

On March 26, 2012, the Company received a subpoena from the Defense Criminal Investigative Service seeking documents related to one of the Company’s contracts for the period of January 1, 2007 through March 26, 2012. The Company has provided documents responsive to the subpoena and is cooperating fully with the government’s investigation. The Company has accrued its current best estimate of the likely outcome within its estimated range of zero to $3.9 million.

On April 9, 2012, the Company received a letter from the Department of Justice (DoJ) informing the Company that the DoJ is investigating whether the Company violated the civil False Claims Act by submitting false claims to receive federal funds pursuant to a GSA contract. Specifically, the DoJ is investigating whether the Company failed to comply with contract requirements and applicable regulations by improperly billing for certain contracting personnel under the contract. The Company has not accrued any liability as based on its present knowledge of the facts, it does not believe an unfavorable outcome is probable.

We are also pursuing appeals at the ASBCA of determinations and demands made by the DCMA associated with questioned direct costs from DCAA audits of our incurred cost submissions for our fiscal years ending June 30 2006, 2007, and 2008. The Company has accrued its current best estimate of the likely outcome within its estimated range of zero to $1.0 million.

Virginia Sales and Use Tax Audit

The Company is under audit for sales and use tax related issues by the Commonwealth of Virginia. The Company has accrued its current best estimate of the likely outcome within its estimated range of $1.0 million to $2.5 million.

Stock-Based Compensation

6 Months Ended

Dec. 31, 2016

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation

8.	Stock-Based Compensation

Stock-based compensation expense recognized, together with the income tax benefits recognized, is as follows (in thousands):

	Three Months Ended				Six Months Ended
	December 31,				December 31,
	2016		2015		2016		2015
Total stock-based compensation related to RSUs included in indirect costs and selling expense	$	5,660	$	4,835	$	10,557	$	8,473
Income tax benefit recognized for stock-based compensation expense	$	2,125	$	1,734	$	3,883	$	3,177

Under the terms of its 2016 Amended and Restated Incentive Compensation Plan (the 2016 Plan), the Company may issue, among others, non-qualified stock options, restricted stock, RSUs, SSARs, and performance awards, collectively referred to herein as equity instruments. The 2016 Plan was approved by the Company’s stockholders in November 2016 and amended and restated the 2006 Stock Incentive Plan (the 2006 Plan) which was due to expire at the end of the ten-year period. Previous grants were made under the 2006 Plan, and equity instruments granted prior to approval of the 2016 Plan continue to be governed by the terms of the 2006 Plan. During the periods presented all equity instrument grants were made in the form of RSUs. Other than performance-based RSUs (PRSUs) which contain a market-based element, the fair value of RSU grants was determined based on the closing price of a share of the Company’s common stock on the date of grant. The fair value of RSUs with market-based vesting features was also measured on the grant date, but was done so using a binomial lattice model.

Annual grants under the 2016 Plan, and previously the 2006 Plan, are generally made to the Company’s key employees during the first quarter of the Company’s fiscal year and to members of the Company’s Board of Directors during the second quarter of the Company’s fiscal year. With the approval of its Chief Executive Officer, the Company also issues equity instruments to strategic new hires and to employees who have demonstrated superior performance.

In September 2014, the Company made its annual grant to key employees consisting of 180,570 PRSUs. The final number of such PRSUs that are earned by participants and vest is based on the achievement of a specified earnings per share (EPS) for the year ended June 30, 2015 and on the average share price of Company stock for the 90 day period ending September 23, 2015, 2016 and 2017 as compared to the average share price for the 90 day period ended September 23, 2014. The specified EPS for the year ended June 30, 2015 was met and the average share price of the Company’s stock for the 90 day periods ending September 23, 2015 and September 23, 2016 exceeded the average share price of the Company’s stock for the 90 day period ended September 23, 2014, resulting in an additional 26,957 RSUs earned by participants.

In September 2015, the Company made its annual grant to key employees consisting of 208,160 PRSUs. The final number of such PRSUs that are earned by participants and vest is based on the achievement of a specified EPS for the year ending June 30, 2016 and on the average share price of Company stock for the 90 day periods ending September 18, 2016, 2017 and 2018 as compared to the average share price for the 90 day period ended September 18, 2015. The specified EPS for the year ended June 30, 2016 was met and the average share price of the Company’s stock for the 90 day period ending September 18, 2016 exceeded the average share price of the Company’s stock for the 90 day period ended September 18, 2015, resulting in an additional 11,811 RSUs earned by participants.

In September 2016, the Company made its annual grant to its key employees consisting of 193,420 PRSUs. The final number of such PRSUs that are earned by participants and vest is based on the achievement of a specified EPS for the year ended June 30, 2017 and on the average share price of Company stock for the 90 day period ending September 30, 2017, 2018 and 2019 as compared to the average share price for the 90 day period ended September 30, 2016. If EPS for the year ending June 30, 2017 exceeds the specified EPS and the average share price of the Company’s stock for the 90 day period ending September 30, 2017, 2018 and 2019 exceeds the average share price of the Company’s stock for the 90 day period ended September 30, 2016 by 100 percent or more, then an additional 193,420 could be earned by participants. This is the maximum number of additional RSUs that can be earned related to the September 2016 annual grant. In addition to the performance and market conditions, there is a service vesting condition which stipulates that 50 percent of the earned award will vest on October 1, 2019 and 50 percent of the earned award will vest on October 1, 2020, in both cases dependent upon continuing service by the grantee as an employee of the Company, unless the grantee is eligible for earlier vesting upon retirement or certain other events.

The total number of shares authorized by shareholders for future grants under the 2016 Plan was reset in November 2016 to 1,200,000. The aggregate number of grants that may be made may exceed this approved amount as forfeited SSARs, stock options, restricted stock and RSUs, and vested but unexercised SSARs and stock options that expire, become available for future grants. As of December 31, 2016, cumulative grants of 8,056 equity instruments underlying the shares authorized in the 2016 Plan have been awarded, and none of these instruments have been forfeited.

Activity related to RSUs during the six months ended December 31, 2016 is as follows:

	RSUs
Outstanding, June 30, 2016		873,854
Granted		223,108
Vested		(106,977	)
Forfeited		(22,130	)
Outstanding, December 31, 2016		967,855
Weighted-average grant date fair value for RSUs	$	101.52

As of December 31, 2016, there was $45.4 million of total unrecognized compensation costs related to RSUs scheduled to be recognized over a weighted-average period of 2.8 years.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Earnings Per Share

6 Months Ended

Dec. 31, 2016

Earnings Per Share [Abstract]

Earnings Per Share

9.	Earnings Per Share

ASC 260, Earnings Per Share (ASC 260), requires dual presentation of basic and diluted earnings per share on the face of the income statement. Basic earnings per share excludes dilution and is computed by dividing income by the weighted-average number of common shares outstanding for the period. Diluted earnings per share reflects potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock but not securities that are anti-dilutive, including stock options and SSARs with an exercise price greater than the average market price of the Company’s common stock. Using the treasury stock method, diluted earnings per share include the incremental effect of SSARs, stock options, restricted shares, and those RSUs that are no longer subject to a market or performance condition. The PRSUs granted in September 2016 are excluded from the calculation of diluted earnings per share as the underlying shares are considered to be contingently issuable shares. These shares will be included in the calculation of diluted earnings per share beginning in the first reporting period in which the performance metric is achieved. The chart below shows the calculation of basic and diluted earnings per share (in thousands, except per share amounts):

	Three Months Ended				Six Months Ended
	December 31,				December 31,
	2016		2015		2016		2015
Net income	$	42,420	$	30,452	$	79,083	$	65,084
Weighted-average number of basic shares outstanding during the period		24,387		24,246		24,363		24,227
Dilutive effect of SSARs/stock options and RSUs after application of treasury stock method		682		540		635		527
Weighted-average number of diluted shares outstanding during the period		25,069		24,786		24,998		24,754
Basic earnings per share	$	1.74	$	1.26	$	3.25	$	2.69
Diluted earnings per share	$	1.69	$	1.23	$	3.16	$	2.63

Income Taxes

6 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Income Taxes

10.	Income Taxes

The Company is subject to income taxes in the U.S. and various state and foreign jurisdictions. Tax statutes and regulations within each jurisdiction are subject to interpretation and require the application of significant judgment. The Company’s total liability for unrecognized tax benefits as of December 31, 2016 and June 30, 2016 was $0.4 million for both periods. The $0.4 million unrecognized tax benefit at December 31, 2016, if recognized, would impact the Company’s effective tax rate.

Business Segment Information

6 Months Ended

Dec. 31, 2016

Segment Reporting [Abstract]

Business Segment Information

11.	Business Segment Information

The Company reports operating results and financial data in two segments: domestic operations and international operations. Domestic operations provide information solutions and services to its customers. Its customers are primarily U.S. federal government agencies. Other customers of the Company’s domestic operations include state and local governments and commercial enterprises. The Company places employees in locations around the world in support of its clients. International operations offer services to both commercial and non-U.S. government customers primarily within the Company’s business systems and enterprise IT markets. The Company evaluates the performance of its operating segments based on net income. Summarized financial information concerning the Company’s reportable segments is as follows (in thousands):

	Domestic		International		Total
Three Months Ended December 31, 2016
Revenue from external customers	$	1,024,025	$	33,505	$	1,057,530
Net income		38,732		3,688		42,420
Three Months Ended December 31, 2015
Revenue from external customers	$	793,542	$	36,895	$	830,437
Net income		26,741		3,711		30,452
Six Months Ended December 31, 2016
Revenue from external customers	$	2,062,916	$	67,894	$	2,130,810
Net income attributable to CACI		72,374		6,709		79,083
Six Months Ended December 31, 2015
Revenue from external customers	$	1,579,220	$	73,659	$	1,652,879
Net income attributable to CACI		58,676		6,408		65,084

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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+ Details

Fair Value of Financial Instruments

6 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Fair Value of Financial Instruments

12.	Fair Value of Financial Instruments

ASC 820, Fair Value Measurements and Disclosures, defines fair value, establishes a framework for measuring fair value and expands disclosures about fair value measurements. Fair value is the price that would be received to sell an asset or paid to transfer a liability between market participants in an orderly transaction. The market in which the reporting entity would sell the asset or transfer the liability with the greatest volume and level of activity for the asset or liability is known as the principal market. When no principal market exists, the most advantageous market is used. This is the market in which the reporting entity would sell the asset or transfer the liability with the price that maximizes the amount that would be received or minimizes the amount that would be paid. Fair value is based on assumptions market participants would make in pricing the asset or liability. Generally, fair value is based on observable quoted market prices or derived from observable market data when such market prices or data are available. When such prices or inputs are not available, the reporting entity should use valuation models.

The Company’s financial assets and liabilities recorded at fair value on a recurring basis are categorized based on the priority of the inputs used to measure fair value. The inputs used in measuring fair value are categorized into three levels, as follows:

•

Level 1 Inputs – unadjusted quoted prices in active markets for identical assets or liabilities.

•

Level 2 Inputs – unadjusted quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets and liabilities in markets that are not active, inputs other than quoted prices that are observable, and inputs derived from or corroborated by observable market data.

•

Level 3 Inputs – amounts derived from valuation models in which unobservable inputs reflect the reporting entity’s own assumptions about the assumptions of market participants that would be used in pricing the asset or liability.

The Company’s financial instruments measured at fair value included interest rate swap agreements and contingent consideration in connection with business combinations. The following table summarizes the financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2016 and June 30, 2016, and the level they fall within the fair value hierarchy (in thousands):

			December 31,		June 30,
	Financial Statement	Fair Value	2016		2016
Description of Financial Instrument	Classification	Hierarchy	Fair Value
Contingent consideration	Other accrued expenses and current liabilities	Level 3	$	3,569	$	—
Contingent consideration	Other long-term liabilities	Level 3	$	11,449	$	15,171
Interest rate swap agreements	Other long-term assets	Level 2	$	5,852	$	—
Interest rate swap agreements	Other accrued expenses and current liabilities	Level 2	$	345	$	—
Interest rate swap agreements	Other long-term liabilities	Level 2	$	5,844	$	21,609

Changes in the fair value of the interest rate swap agreements are recorded as a component of accumulated other comprehensive income or loss.

Various acquisitions completed during FY16 contained provisions requiring that the Company pay contingent consideration in the event the acquired businesses achieved certain specified earnings results during the two and three year periods subsequent to each acquisition. The Company determined the fair value of the contingent consideration as of each acquisition date using a valuation model which included the evaluation of the most likely outcome and the application of an appropriate discount rate. At the end of each reporting period, the fair value of the contingent consideration was remeasured and any changes were recorded in indirect costs and selling expenses. During the three and six months ended December 31, 2016, this remeasurement resulted in a change to the liability recorded of $0.4 million and $0.8 million, respectively.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Accounting Policies (Policies)	6 Months Ended
Accounting Policies (Policies)	Dec. 31, 2016
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited consolidated financial statements of CACI International Inc and subsidiaries (CACI or the Company) have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission (SEC) and include the assets, liabilities, results of operations, comprehensive income and cash flows for the Company, including its subsidiaries and ventures that are majority-owned or otherwise controlled by the Company. Certain information and note disclosures normally included in the annual financial statements prepared in accordance with U.S. generally accepted accounting principles (GAAP) have been condensed or omitted pursuant to those rules and regulations, although the Company believes that the disclosures made are adequate to make the information presented not misleading. All intercompany balances and transactions have been eliminated in consolidation. The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable and amounts included in other current assets and current liabilities that meet the definition of a financial instrument approximate fair value because of the short-term nature of these amounts. The fair value of the Company’s debt outstanding as of December 31, 2016 under its bank credit facility approximates its carrying value. The fair value of the Company’s debt under its bank credit facility was estimated using Level 2 inputs based on market data of companies with a corporate rating similar to CACI’s that have recently priced credit facilities. See Notes 6 and 12. In the opinion of management, the accompanying unaudited consolidated financial statements reflect all adjustments and reclassifications (all of which are of a normal, recurring nature) that are necessary for the fair presentation of the periods presented. It is suggested that these unaudited consolidated financial statements be read in conjunction with the audited consolidated financial statements and the notes thereto included in the Company’s latest annual report to the SEC on Form 10-K for the year ended June 30, 2016. The results of operations for the three and six months ended December 31, 2016 are not necessarily indicative of the results to be expected for any subsequent interim period or for the full fiscal year.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In January 2017, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2017-01, Clarifying the Definition of a Business, which revises the definition of a business and provides guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The guidance is effective for the fiscal year, and interim periods within that fiscal year, beginning after December 15, 2017. The Company is currently evaluating the impact of the adoption of this standard on its consolidated financial statements. In March 2016, the FASB issued ASU No. 2016-09, Improvements to Employee Share-Based Payment Accounting, which simplifies several aspects of the accounting for share-based payments, including income tax consequences and classification on the statement of cash flows. Under the new standard, all excess tax benefits and tax deficiencies will be recognized as income tax expense or benefit in the income statement as discrete items in the reporting period in which they occur. Additionally, excess tax benefits will be classified as an operating activity on the statement of cash flows. In regards to forfeitures, the entity can make an accounting policy election to either recognize forfeitures as they occur or estimate the number of awards expected to be forfeited. The guidance in ASU 2016-09 is effective for the fiscal year, and interim periods within that fiscal year, beginning after December 15, 2016. Early adoption is permitted in any interim or annual period, with adjustments reflected as of the beginning of the fiscal year of adoption. The Company early adopted this standard during the fourth quarter of FY16, and therefore reported the impact as though the ASU had been adopted on July 1, 2015. Upon adoption, the Company recognized excess tax benefits of $0.1 million and $0.9 million during the three and six months ended December 31, 2015 as a reduction to tax expense in the Consolidated Statements of Operations, as though ASU 2016-09 had been in effect since the beginning of FY16. Consequently, this resulted in an increase in net income, an increase in earnings per share and a decrease in the annual effective tax rate. In addition, the excess tax benefits that were previously presented as a financing activity on the Consolidated Statements of Cash Flows are now presented as an operating activity, with periods prior to FY16 retrospectively adjusted. With respect to forfeitures, the Company will continue to estimate the number of awards expected to be forfeited in accordance with our existing accounting policy. In February 2016, the FASB issued ASU No. 2016-02, Leases, which amends the existing guidance on accounting for leases. The new standard requires lessees to put virtually all leases on the balance sheet by recognizing lease assets and lease liabilities. Lessor accounting is largely unchanged from that applied under previous guidance. The amended guidance is effective for the fiscal year, and interim periods within that fiscal year, beginning after December 15, 2018, and requires a modified retrospective approach. Early adoption is permitted. The Company is currently evaluating the impact of the adoption of this standard on its consolidated financial statements.

Acquisitions (Tables)

6 Months Ended

Dec. 31, 2016

Business Combinations [Abstract]

Assets Acquired and Liabilities Assumed

Cash and cash equivalents	$	2,596
Accounts receivable		211,055
Prepaid expenses and other current assets		14,628
Property and equipment		21,320
Intangible assets		110,500
Goodwill		359,088
Other long-term assets		437
Accounts payable		(57,616	)
Accrued compensation and benefits		(38,953	)
Other accrued expenses and current liabilities		(38,116	)
Deferred income taxes		(37,796	)
Other long-term liabilities		(5,280	)
Total estimated consideration	$	541,863

Intangible Assets (Tables)

6 Months Ended

Dec. 31, 2016

Finite Lived Intangible Assets Net [Abstract]

Schedule of Intangible Assets

Intangible assets consisted of the following (in thousands):

	December 31,			June 30,
	2016			2016
Customer contracts and related customer relationships	$	635,004		$	635,826
Acquired technologies		28,436			28,074
Covenants not to compete		3,278			3,321
Other		1,535			1,551
Intangible assets		668,253			668,772
Accumulated amortization:
Customer contracts and related customer relationships		(383,327	)		(363,412	)
Acquired technologies		(26,147	)		(25,693	)
Covenants not to compete		(3,231	)		(3,245	)
Other		(1,067	)		(1,050	)
Less accumulated amortization		(413,772	)		(393,400	)
Total intangible assets, net	$	254,481		$	275,372

Expected Amortization Expense

Expected amortization expense for the remainder of the fiscal year ending June 30, 2017, and for each of the fiscal years thereafter, is as follows (in thousands):

Fiscal year ending June 30,	Amount
2017 (six months)	$	19,383
2018		36,208
2019		31,551
2020		27,088
2021		23,896
Thereafter		116,355
Total intangible assets, net	$	254,481

Goodwill (Tables)

6 Months Ended

Dec. 31, 2016

Goodwill [Abstract]

Rollforward of Goodwill

The changes in the carrying amount of goodwill for the year ended June 30, 2016 and the six months ended December 31, 2016 are as follows (in thousands):

	Domestic			International			Total
Balance at June 30, 2015	$	2,108,768		$	81,048		$	2,189,816
Business acquisitions		378,380			29,939			408,319
Foreign currency translation		—			(12,792	)		(12,792	)
Balance at June 30, 2016		2,487,148			98,195			2,585,343
Business acquisitions		(8,635	)		2,220			(6,415	)
Foreign currency translation		—			(7,631	)		(7,631	)
Balance at December 31, 2016	$	2,478,513		$	92,784		$	2,571,297

Long-term Debt (Tables)

6 Months Ended

Dec. 31, 2016

Long Term Debt [Abstract]

Schedule of Long-term Debt

Long-term debt consisted of the following (in thousands):

	December 31,			June 30,
	2016			2016
Bank credit facility – term loans	$	1,019,341		$	1,032,833
Bank credit facility – revolver loans		355,000			440,000
Principal amount of long-term debt		1,374,341			1,472,833
Less unamortized debt issuance costs		(14,537	)		(16,789	)
Total long-term debt		1,359,804			1,456,044
Less current portion		(67,456	)		(53,965	)
Long-term debt, net of current portion	$	1,292,348		$	1,402,079

Cash Flow Hedges

The effect of derivative instruments in the consolidated statements of operations and accumulated other comprehensive loss for the three and six months ended December 31, 2016 and 2015 is as follows (in thousands):

	Three Months Ended				Six Months Ended
	December 31,				December 31,
	2016		2015		2016		2015
Gain (loss) recognized in other comprehensive income	$	7,920	$	1,440	$	8,525	$	(4,016	)
Amounts reclassified to earnings from accumulated other comprehensive loss		2,125		2,392		4,374		4,814
Net current period other comprehensive income	$	10,045	$	3,832	$	12,899	$	798

Aggregate Maturities of Long-term Debt

The aggregate maturities of long-term debt at December 31, 2016 are as follows (in thousands):

Twelve months ending December 31,
2017	$	67,456
2018		80,947
2019		107,930
2020		1,118,008
Principal amount of long-term debt		1,374,341
Less unamortized debt issuance costs		(14,537	)
Total long-term debt	$	1,359,804

Stock-Based Compensation (Tables)

6 Months Ended

Dec. 31, 2016

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation Expense Recognized

Stock-based compensation expense recognized, together with the income tax benefits recognized, is as follows (in thousands):

	Three Months Ended				Six Months Ended
	December 31,				December 31,
	2016		2015		2016		2015
Total stock-based compensation related to RSUs included in indirect costs and selling expense	$	5,660	$	4,835	$	10,557	$	8,473
Income tax benefit recognized for stock-based compensation expense	$	2,125	$	1,734	$	3,883	$	3,177

Schedule of Activity Related to RSUs

Activity related to RSUs during the six months ended December 31, 2016 is as follows:

	RSUs
Outstanding, June 30, 2016		873,854
Granted		223,108
Vested		(106,977	)
Forfeited		(22,130	)
Outstanding, December 31, 2016		967,855
Weighted-average grant date fair value for RSUs	$	101.52

Earnings Per Share (Tables)

6 Months Ended

Dec. 31, 2016

Earnings Per Share [Abstract]

Calculation of Basic and Diluted Earnings per Share

The chart below shows the calculation of basic and diluted earnings per share (in thousands, except per share amounts):

	Three Months Ended				Six Months Ended
	December 31,				December 31,
	2016		2015		2016		2015
Net income	$	42,420	$	30,452	$	79,083	$	65,084
Weighted-average number of basic shares outstanding during the period		24,387		24,246		24,363		24,227
Dilutive effect of SSARs/stock options and RSUs after application of treasury stock method		682		540		635		527
Weighted-average number of diluted shares outstanding during the period		25,069		24,786		24,998		24,754
Basic earnings per share	$	1.74	$	1.26	$	3.25	$	2.69
Diluted earnings per share	$	1.69	$	1.23	$	3.16	$	2.63

Business Segment Information (Tables)

6 Months Ended

Dec. 31, 2016

Segment Reporting [Abstract]

Summarized Financial Information of Reportable Segments

Summarized financial information concerning the Company’s reportable segments is as follows (in thousands):

	Domestic		International		Total
Three Months Ended December 31, 2016
Revenue from external customers	$	1,024,025	$	33,505	$	1,057,530
Net income		38,732		3,688		42,420
Three Months Ended December 31, 2015
Revenue from external customers	$	793,542	$	36,895	$	830,437
Net income		26,741		3,711		30,452
Six Months Ended December 31, 2016
Revenue from external customers	$	2,062,916	$	67,894	$	2,130,810
Net income attributable to CACI		72,374		6,709		79,083
Six Months Ended December 31, 2015
Revenue from external customers	$	1,579,220	$	73,659	$	1,652,879
Net income attributable to CACI		58,676		6,408		65,084

Fair Value of Financial Instruments (Tables)

6 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Recurring Fair Value Measurements

The following table summarizes the financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2016 and June 30, 2016, and the level they fall within the fair value hierarchy (in thousands):

			December 31,		June 30,
	Financial Statement	Fair Value	2016		2016
Description of Financial Instrument	Classification	Hierarchy	Fair Value
Contingent consideration	Other accrued expenses and current liabilities	Level 3	$	3,569	$	—
Contingent consideration	Other long-term liabilities	Level 3	$	11,449	$	15,171
Interest rate swap agreements	Other long-term assets	Level 2	$	5,852	$	—
Interest rate swap agreements	Other accrued expenses and current liabilities	Level 2	$	345	$	—
Interest rate swap agreements	Other long-term liabilities	Level 2	$	5,844	$	21,609

Recent Accounting Pronouncements (Detail Textual) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Dec. 31, 2015	Dec. 31, 2015
Accounting standards update 2016-09
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Excess tax benefits recognized	$ 0.1	$ 0.9

Acquisitions (Detail Textual) - USD ($) $ in Thousands			6 Months Ended
Acquisitions (Detail Textual) - USD ($) $ in Thousands	Oct. 01, 2016	Feb. 01, 2016	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016	Jun. 30, 2015
Business Acquisition [Line Items]
Proceeds from revolver borrowings			$ 240,500	$ 154,488
Goodwill			$ 2,571,297		$ 2,585,343	$ 2,189,816
Customer contracts and related customer relationships
Business Acquisition [Line Items]
Amortization period of acquired intangible assets			14 years 1 month 6 days
Revolving Credit Facility
Business Acquisition [Line Items]
Proceeds from revolver borrowings		$ 250,000
Term loans
Business Acquisition [Line Items]
Proceeds from term loan borrowings		$ 300,000
NSS Acquisition
Business Acquisition [Line Items]
Percentage of outstanding shares acquired		100.00%
Cash consideration		$ 550,000
Consideration, initial net working capital payment		11,200
Consideration, net working capital refund received		13,600
Consideration, expected refund for tax-related adjustments		5,700
Measurement period adjustments, other current assets			$ 2,600
Measurement period adjustments, receivables			1,200
Measurement period adjustments, other accrued expenses			600
Measurement period adjustments, purchase consideration			5,500
Measurement period adjustments, goodwill			$ 8,600
Business purchase consideration		541,900
Goodwill		359,088
Amount of tax deductible goodwill and intangibles		$ 47,700
NSS Acquisition \| Customer contracts and related customer relationships
Business Acquisition [Line Items]
Amortization period of acquired intangible assets		15 years
NSS Acquisition \| Revolving Credit Facility
Business Acquisition [Line Items]
Proceeds from revolver borrowings		$ 250,000
NSS Acquisition \| Term loans
Business Acquisition [Line Items]
Proceeds from term loan borrowings		$ 300,000
Business in United Kingdom
Business Acquisition [Line Items]
Business purchase consideration	$ 2,800

Acquisitions - Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Jun. 30, 2016	Feb. 01, 2016	Jun. 30, 2015
Business Acquisition [Line Items]
Goodwill	$ 2,571,297	$ 2,585,343		$ 2,189,816
NSS Acquisition
Business Acquisition [Line Items]
Cash and cash equivalents			$ 2,596
Accounts receivable			211,055
Prepaid expenses and other current assets			14,628
Property and equipment			21,320
Intangible assets			110,500
Goodwill			359,088
Other long-term assets			437
Accounts payable			(57,616)
Accrued compensation and benefits			(38,953)
Other accrued expenses and current liabilities			(38,116)
Deferred income taxes			(37,796)
Other long-term liabilities			(5,280)
Total estimated consideration			$ 541,863

Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Jun. 30, 2016
Finite Lived Intangible Assets [Line Items]
Intangible assets	$ 668,253	$ 668,772
Less accumulated amortization	(413,772)	(393,400)
Total intangible assets, net	254,481	275,372
Customer contracts and related customer relationships
Finite Lived Intangible Assets [Line Items]
Intangible assets	635,004	635,826
Less accumulated amortization	(383,327)	(363,412)
Acquired technologies
Finite Lived Intangible Assets [Line Items]
Intangible assets	28,436	28,074
Less accumulated amortization	(26,147)	(25,693)
Covenants not to compete
Finite Lived Intangible Assets [Line Items]
Intangible assets	3,278	3,321
Less accumulated amortization	(3,231)	(3,245)
Other
Finite Lived Intangible Assets [Line Items]
Intangible assets	1,535	1,551
Less accumulated amortization	$ (1,067)	$ (1,050)

Intangible Assets (Detail Textual)	6 Months Ended
Intangible Assets (Detail Textual)	Dec. 31, 2016
Minimum
Finite Lived Intangible Assets [Line Items]
Intangible asset amortization period	1 year
Maximum
Finite Lived Intangible Assets [Line Items]
Intangible asset amortization period	15 years
Customer contracts and related customer relationships
Finite Lived Intangible Assets [Line Items]
Weighted-average amortization period	14 years 1 month 6 days
Weighted-average remaining amortization period	11 years 7 months 6 days
Acquired technologies
Finite Lived Intangible Assets [Line Items]
Weighted-average amortization period	9 years 7 months 6 days
Weighted-average remaining amortization period	6 years 1 month 6 days

Intangible Assets - Expected Amortization Expense (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Jun. 30, 2016
Finite Lived Intangible Assets Net [Abstract]
2017 (six months)	$ 19,383
2018	36,208
2019	31,551
2020	27,088
2021	23,896
Thereafter	116,355
Total intangible assets, net	$ 254,481	$ 275,372

Goodwill - Rollforward of Goodwill (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2016	Jun. 30, 2016
Goodwill [Roll Forward]
Balance	$ 2,585,343	$ 2,189,816
Business acquisitions	(6,415)	408,319
Foreign currency translation	(7,631)	(12,792)
Balance	2,571,297	2,585,343
Domestic
Goodwill [Roll Forward]
Balance	2,487,148	2,108,768
Business acquisitions	(8,635)	378,380
Balance	2,478,513	2,487,148
International
Goodwill [Roll Forward]
Balance	98,195	81,048
Business acquisitions	2,220	29,939
Foreign currency translation	(7,631)	(12,792)
Balance	$ 92,784	$ 98,195

Long-term Debt - Schedule of Long-term Debt (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Jun. 30, 2016
Debt Instrument [Line Items]
Principal amount of long-term debt	$ 1,374,341	$ 1,472,833
Less unamortized debt issuance costs	(14,537)	(16,789)
Total long-term debt	1,359,804	1,456,044
Less current portion	(67,456)	(53,965)
Long-term debt, net of current portion	1,292,348	1,402,079
Bank credit facility - term loans
Debt Instrument [Line Items]
Principal amount of long-term debt	1,019,341	1,032,833
Bank credit facility - revolver loans
Debt Instrument [Line Items]
Principal amount of long-term debt	$ 355,000	$ 440,000

Long-term Debt (Detail Textual)		6 Months Ended
Long-term Debt (Detail Textual)	Feb. 01, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jun. 30, 2016 USD ($)
Debt Instrument [Line Items]
Proceeds from revolver borrowings		$ 240,500,000	$ 154,488,000
Outstanding amount under Credit Facility		1,374,341,000		$ 1,472,833,000
Cash Flow Hedging \| Interest Rate Swap
Debt Instrument [Line Items]
Aggregate notional amount		900,000,000
Bank Credit Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		$ 1,981,300,000
Credit facility borrowing capacity, description		At any time and so long as no default has occurred, the Company has the right to increase the Revolving Facility or the Term Loan in an aggregate principal amount of up to the greater of $400.0 million or an amount subject to 2.75 times senior secured leverage, calculated assuming the Revolving Facility is fully drawn, with applicable lender approvals.
Credit Facility optional increases to borrowing capacity		$ 400,000,000
Ratio that restricts optional increases to borrowing capacity		2.75
Outstanding borrowings interest rate		3.22%
Revolving Credit Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		$ 850,000,000
Proceeds from revolver borrowings	$ 250,000,000
Outstanding amount under Credit Facility		355,000,000		440,000,000
Term loans
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		1,131,300,000
Proceeds from term loan borrowings	$ 300,000,000
Outstanding amount under Credit Facility		$ 1,019,341,000		$ 1,032,833,000
Term loan period		5 years
Loan maturity date		Jun. 01, 2020
Term loan frequency of payment		quarterly
Term loans \| Principal Payment Through June 30, 2018
Debt Instrument [Line Items]
Term loan principal payment		$ 13,500,000
Term loans \| Principal Payment Thereafter June 30, 2018
Debt Instrument [Line Items]
Term loan principal payment		27,000,000
Same-Day Swing Line Loan Revolving Credit Sub Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		100,000,000
Stand-By Letters Of Credit Revolving Credit Sub Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity		25,000,000
Outstanding Letters of Credit		$ 400,000

Long-term Debt - Cash Flow Hedges (Detail 1) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Long Term Debt [Abstract]
Gain (loss) recognized in other comprehensive income	$ 7,920	$ 1,440	$ 8,525	$ (4,016)
Amounts reclassified to earnings from accumulated other comprehensive loss	2,125	2,392	4,374	4,814
Net current period other comprehensive income	$ 10,045	$ 3,832	$ 12,899	$ 798

Long-term Debt - Aggregate Maturities of Long-Term Debt (Detail 2) - USD ($) $ in Thousands	Dec. 31, 2016	Jun. 30, 2016
Long Term Debt [Abstract]
2017	$ 67,456
2018	80,947
2019	107,930
2020	1,118,008
Principal amount of long-term debt	1,374,341	$ 1,472,833
Less unamortized debt issuance costs	(14,537)	(16,789)
Total long-term debt	$ 1,359,804	$ 1,456,044

Commitments and Contingencies (Detail Textual)	Dec. 31, 2016 USD ($)
Minimum \| Government Contracting
Loss Contingencies [Line Items]
Estimated amount of possible loss	$ 0
Minimum \| Government Contracting \| Incurred Cost Submissions
Loss Contingencies [Line Items]
Estimated amount of possible loss	0
Minimum \| Virginia Sales and Use Tax Audit
Loss Contingencies [Line Items]
Estimated amount of possible loss	1,000,000
Maximum \| Government Contracting
Loss Contingencies [Line Items]
Estimated amount of possible loss	3,900,000
Maximum \| Government Contracting \| Incurred Cost Submissions
Loss Contingencies [Line Items]
Estimated amount of possible loss	1,000,000
Maximum \| Virginia Sales and Use Tax Audit
Loss Contingencies [Line Items]
Estimated amount of possible loss	$ 2,500,000

Stock-Based Compensation - Expense Recognized (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Stock-based compensation included in indirect costs and selling expense:
Total stock-based compensation related to RSUs included in indirect costs and selling expense	$ 5,660	$ 4,835	$ 10,557	$ 8,473
Income tax benefit recognized for stock-based compensation expense	$ 2,125	$ 1,734	$ 3,883	$ 3,177

Stock-Based Compensation (Detail Textual) $ in Millions	6 Months Ended
Stock-Based Compensation (Detail Textual) $ in Millions	Dec. 31, 2016 USD ($) shares
2006 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan, expiration period	10 years
2006 Stock Incentive Plan \| PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period to establish average share price for performance measurement	90 days
2006 Stock Incentive Plan \| PRSUs \| September 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSUs granted	180,570
2006 Stock Incentive Plan \| PRSUs \| September 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSUs granted	208,160
Period to establish average share price for performance measurement	90 days
2006 Stock Incentive Plan \| PRSUs \| September2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSUs granted	193,420
Period to establish average share price for performance measurement	90 days
2006 Stock Incentive Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost \| $	$ 45.4
Weighted-average period to recognize unrecognized compensation cost (in years)	2 years 9 months 18 days
2006 Stock Incentive Plan \| RSUs \| October 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of awards	50.00%
2006 Stock Incentive Plan \| RSUs \| October 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage of awards	50.00%
2006 Stock Incentive Plan \| RSUs \| September 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional awards to be issued pursuant to condition	26,957
2006 Stock Incentive Plan \| RSUs \| September 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional awards to be issued pursuant to condition	11,811
2006 Stock Incentive Plan \| RSUs \| September2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional awards to be issued pursuant to condition	193,420
Description of vesting of awards	In addition to the performance and market conditions, there is a service vesting condition which stipulates that 50 percent of the earned award will vest on October 1, 2019 and 50 percent of the earned award will vest on October 1, 2020
2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative grants of equity instruments awarded	8,056
Number of cumulative equity instruments forfeited	0
2016 Plan \| November 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for future grants	1,200,000

Stock-Based Compensation - Schedule of Activity Related to RSUs (Detail 1) - RSUs	6 Months Ended
	Dec. 31, 2016 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, June 30, 2016	873,854
Granted	223,108
Vested	(106,977)
Forfeited	(22,130)
Outstanding, December 31, 2016	967,855
Weighted-average grant date fair value for RSUs \| $ / shares	$ 101.52

Earnings Per Share - Calculation of Basic and Diluted Earnings per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share [Abstract]
Net income	$ 42,420	$ 30,452	$ 79,083	$ 65,084
Weighted-average number of basic shares outstanding during the period	24,387	24,246	24,363	24,227
Dilutive effect of SSARs/stock options and RSUs after application of treasury stock method	682	540	635	527
Weighted-average number of diluted shares outstanding during the period	25,069	24,786	24,998	24,754
Basic earnings per share	$ 1.74	$ 1.26	$ 3.25	$ 2.69
Diluted earnings per share	$ 1.69	$ 1.23	$ 3.16	$ 2.63

Income Taxes (Detail Textual) - USD ($) $ in Millions	Dec. 31, 2016	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Liability for unrecognized tax benefits	$ 0.4	$ 0.4
Unrecognized tax benefit that would impact the company's effective tax rate	$ 0.4

Business Segment Information (Detail Textual)	6 Months Ended
Business Segment Information (Detail Textual)	Dec. 31, 2016 Segment
Segment Reporting [Abstract]
Number of reportable segments	2

Business Segment Information - Summarized Financial Information of Reportable Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting Information [Line Items]
Revenue from external customers	$ 1,057,530	$ 830,437	$ 2,130,810	$ 1,652,879
Net income	42,420	30,452	79,083	65,084
Net income attributable to CACI	42,420	30,452	79,083	65,084
Domestic
Segment Reporting Information [Line Items]
Revenue from external customers	1,024,025	793,542	2,062,916	1,579,220
Net income	38,732	26,741
Net income attributable to CACI			72,374	58,676
International
Segment Reporting Information [Line Items]
Revenue from external customers	33,505	36,895	67,894	73,659
Net income	$ 3,688	$ 3,711
Net income attributable to CACI			$ 6,709	$ 6,408

Fair Value of Financial Instruments - Recurring Fair Value Measurements (Detail) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Dec. 31, 2016	Jun. 30, 2016
Other accrued expenses and current liabilities \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	$ 3,569
Other accrued expenses and current liabilities \| Level 2 \| Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements	345
Other long-term liabilities \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	11,449	$ 15,171
Other long-term liabilities \| Level 2 \| Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements	5,844	$ 21,609
Other long-term assets \| Level 2 \| Interest Rate Swap
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate swap agreements	$ 5,852

Fair Value of Financial Instruments (Detail Textual) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Dec. 31, 2016	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Business combination contingent consideration period		two and three year periods
Change in fair value of contingent consideration	$ 0.4	$ 0.8