Leidos (LDOS) 10-Q 27 Jul 18 2018 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 29, 2018	Jul. 17, 2018
Document Documentand Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 29, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Trading Symbol	LDOS
Entity Registrant Name	Leidos Holdings, Inc.
Entity Central Index Key	1,336,920
Current Fiscal Year End Date	--12-28
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		150,485,383

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Jun. 29, 2018	Dec. 29, 2017
ASSETS
Cash and cash equivalents	$ 303	$ 390
Receivables, net	1,779	1,831
Inventory, prepaid expenses and other current assets	458	453
Assets held for sale	99	0
Total current assets	2,639	2,674
Property, plant and equipment, net	221	232
Intangible assets, net	749	856
Goodwill	4,887	4,974
Other assets	274	254
Total assets	8,770	8,990
LIABILITIES AND EQUITY
Accounts payable and accrued liabilities	1,461	1,639
Accrued payroll and employee benefits	446	487
Dividends payable	12	17
Income taxes payable	3	4
Long-term debt, current portion	71	55
Liabilities held for sale	22	0
Total current liabilities	2,015	2,202
Long-term debt, net of current portion	2,990	3,056
Deferred tax liabilities	211	220
Other long-term liabilities	136	129
Commitments and contingencies (Notes 20 and 21)
Stockholders’ equity:
Common stock, $.0001 par value, 500 million shares authorized, 150 million and 151 million shares issued and outstanding at June 29, 2018 and December 29, 2017, respectively	0	0
Additional paid-in capital	3,260	3,344
Accumulated earnings (deficit)	133	(7)
Accumulated other comprehensive income	23	33
Total Leidos stockholders’ equity	3,416	3,370
Non-controlling interest	2	13
Total equity	3,418	3,383
Total liabilities and stockholders' equity	$ 8,770	$ 8,990

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jun. 29, 2018	Dec. 29, 2017
Statement of Financial Position [Abstract]
Common stock, par value (dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	150,000,000	151,000,000
Common stock, shares outstanding	150,000,000	151,000,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Income Statement [Abstract]
Revenues	$ 2,529	$ 2,571	$ 4,972	$ 5,151
Cost of revenues	2,152	2,190	4,238	4,423
Selling, general and administrative expenses	174	186	352	367
Integration and restructuring costs	8	22	25	54
Asset impairment charges	0	0	7	0
Equity (earnings) losses of non-consolidated subsidiaries	(4)	7	(8)	0
Operating income	199	166	358	307
Non-operating expense:
Interest expense, net	(35)	(34)	(69)	(70)
Other income, net	1	3	1	6
Income before income taxes	165	135	290	243
Income tax expense	(20)	(37)	(43)	(71)
Net income	145	98	247	172
Less: net income attributable to non-controlling interest	1	0	1	2
Net income attributable to Leidos common stockholders	$ 144	$ 98	$ 246	$ 170
Earnings per share:
Basic (dollars per share)	$ 0.95	$ 0.65	$ 1.62	$ 1.13
Diluted (dollars per share)	0.94	0.64	1.60	1.11
Cash dividends declared per share (dollars per share)	$ 0.32	$ 0.32	$ 0.64	$ 0.64

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 145	$ 98	$ 247	$ 172
Foreign currency translation adjustments	(37)	2	(33)	13
Unrecognized gain (loss) on derivative instruments (Note 15)	4	(2)	14	(1)
Total other comprehensive (loss) income, net of taxes	(33)	0	(19)	12
Comprehensive income	112	98	228	184
Less: comprehensive income attributable to non-controlling interest	1	0	1	2
Comprehensive income attributable to Leidos common stockholders	$ 111	$ 98	$ 227	$ 182

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Leidos Holdings, Inc. stockholders' equity	Shares of common stock	Additional paid-in capital	Accumulated earnings (deficit)	Accumulated other comprehensive income	Non-controlling interest
Balance (shares) at Dec. 30, 2016			150
Balance at Dec. 30, 2016	$ 3,147	$ 3,135		$ 3,316	$ (177)	$ (4)	$ 12
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	172	170			170		2
Other comprehensive income, net of taxes	12	12				12
Issuances of stock (shares)			1
Issuances of stock	10	10		10
Repurchases of stock and other	(25)	(25)		(25)
Dividends declared	(98)	(98)			(98)
Stock-based compensation	20	20		20
Adjustment to original purchase price allocation	3						3
Balance (shares) at Jun. 30, 2017			151
Balance at Jun. 30, 2017	3,241	3,224		3,321	(105)	8	17
Balance (shares) at Dec. 29, 2017			151
Balance at Dec. 29, 2017	3,383	3,370		3,344	(7)	33	13
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	247	246			246		1
Other comprehensive income, net of taxes	(19)	(19)				(19)
Issuances of stock (shares)			1
Issuances of stock	9	9		9
Repurchases of stock and other (shares)			(2)
Repurchases of stock and other	(116)	(116)		(116)
Dividends declared	(98)	(98)			(98)
Stock-based compensation	23	23		23
Purchase of non-controlling interests	(10)						(10)
Other	(2)						(2)
Balance (shares) at Jun. 29, 2018			150
Balance at Jun. 29, 2018	$ 3,418	$ 3,416		$ 3,260	$ 133	$ 23	$ 2

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017
Cash flows from operations:
Net income	$ 247	$ 172
Adjustments to reconcile net income to net cash provided by operations:
Depreciation and amortization	129	162
Stock-based compensation	23	20
Asset impairment charges	7	0
Bad debt expense and other	10	28
Change in assets and liabilities, net of effects of acquisitions:
Receivables	36	(179)
Inventory, prepaid expenses and other current assets	(33)	40
Accounts payable and accrued liabilities	(67)	(123)
Accrued payroll and employee benefits	(35)	(7)
Deferred income taxes and income taxes receivable/payable	(10)	(44)
Other long-term assets/liabilities	(14)	26
Net cash provided by operating activities	293	95
Cash flows from investing activities:
Payments for property, plant and equipment	(28)	(23)
Acquisitions of businesses	(81)	0
Proceeds from sale of assets	0	7
Other	0	2
Net cash used in investing activities	(109)	(14)
Cash flows from financing activities:
Payments of long-term debt	(44)	(69)
Proceeds from issuances of stock	8	7
Repurchases of stock and other	(116)	(25)
Dividend payments	(103)	(102)
Payment of tax indemnification liability	(23)	0
Other	(5)	(1)
Net cash used in financing activities	(283)	(190)
Net decrease in cash, cash equivalents and restricted cash	(99)	(109)
Cash, cash equivalents and restricted cash at beginning of period	422	396
Cash, cash equivalents and restricted cash at end of period	$ 323	$ 287

Nature of Operations and Basis

Nature of Operations and Basis of Presentation	6 Months Ended
	Jun. 29, 2018
Accounting Policies [Abstract]
Nature of Operations and Basis of Presentation	Note 1–Nature of Operations and Basis of Presentation Leidos Holdings, Inc., a Delaware corporation ("Leidos") is a holding company whose direct 100% -owned subsidiaries and principal operating companies are Leidos, Inc. and Leidos Innovations Corporation ("Leidos Innovations"). Leidos is a FORTUNE 500 ® science, engineering and information technology company that provides services and solutions in the defense, intelligence, civil and health markets . Leidos' domestic customers include the U.S. Department of Defense ("DoD"), the U.S. Intelligence Community, the U.S. Department of Homeland Security, the Federal Aviation Administration, the Department of Veterans Affairs, several other U.S. government civil agencies and state and local government agencies . Leidos' international customers include foreign governments and their agencies, primarily located in Australia and the United Kingdom . Unless indicated otherwise, references to the "Company," "we," "us" and "our" refer collectively to Leidos Holdings, Inc. and its consolidated subsidiaries. The Company operates in three reportable segments: Defense Solutions, Civil and Health. Additionally, the Company separately presents the costs associated with corporate functions as Corporate. The Company has a controlling interest in Mission Support Alliance, LLC ("MSA"), a joint venture with Centerra Group, LLC. On January 26, 2018, the Company entered into a Membership Interest Purchase Agreement with Jacobs Engineering Group, Inc. ("Jacob's Group"), whereby the Company purchased 100% of Jacob's Group's 41% outstanding membership interests in MSA. As a result, Leidos increased its controlling ownership in MSA from 47% to 88% . The Company consolidates the financial results for MSA into its unaudited condensed consolidated financial statements. The unaudited condensed consolidated financial statements also include the balances of all voting interest entities in which Leidos has a controlling voting interest (“subsidiaries”) and a variable interest entity ("VIE") in which Leidos is the primary beneficiary. The consolidated balances of the Company’s VIE are not material to the Company’s unaudited condensed consolidated financial statements for the periods presented. Intercompany accounts and transactions between consolidated companies have been eliminated in consolidation. The accompanying unaudited condensed financial information has been prepared in accordance with the rules of the U.S. Securities and Exchange Commission ("SEC") and accounting principles generally accepted in the United States of America ("GAAP"). Certain disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingencies at the date of the financial statements, as well as the reported amounts of revenues and expenses during the reporting periods. Management evaluates these estimates and assumptions on an ongoing basis, including those relating to estimated profitability of long-term contracts, indirect billing rates, allowances for doubtful accounts, inventories, fair value and impairment of intangible assets and goodwill, income taxes, stock-based compensation expense and contingencies. These estimates have been prepared by management on the basis of the most current and best available information; however, actual results could differ materially from those estimates. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments, which consist of normal recurring adjustments, necessary for a fair presentation thereof. The results reported in these unaudited condensed consolidated financial statements are not necessarily indicative of the results that may be expected for the entire year. These unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company's Annual Report on Form 10-K filed on February 23, 2018. Certain amounts in the prior year financial statements have been reclassified to conform to the current year presentation. The Company classifies indirect costs incurred within or allocated to its U.S. government customers as overhead (included in "Cost of revenues") or general administrative expenses in the same manner as such costs are defined in the Company's disclosure statements under U.S. Government Cost Accounting Standards ("CAS"). Effective the beginning of fiscal 2018, the Company established a new CAS structure and revised its disclosure statements accordingly to reflect the related cost accounting practice changes. Consequently, $43 million and $80 million was reclassified from "Cost of revenues" to "Selling, general and administrative expenses" on the condensed consolidated statement of income for the quarter and six months ended June 30, 2017 , respectively. The Company aggregated "Interest income" and "Interest expense" into "Interest expense, net" and "Acquisition and integration costs" and "Restructuring expenses" into "Integration and restructuring costs" on the condensed consolidated statements of income. Additionally, the Company aggregated "Bad debt expense" and "Other" into "Bad debt expense and other" on the Company's condensed consolidated statements of cash flows. Due to the adoption of Accounting Standards Update ("ASU") 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash , changes in restricted cash, which had previously been presented as operating activities, are now included within beginning and ending cash, cash equivalents and restricted cash balances on the statement of cash flows. Consequently, operating cash flows for the six months ended June 30, 2017 , increased by $5 million , with a corresponding increase in the total change in cash, cash equivalents and restricted cash (see " Note 17–Supplementary Cash Flow Information and Restricted Cash " for the disclosures required by this ASU). Due to the adoption of ASU 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments, the Company reclassified $1 million from "Other" within cash flows from operations to "Other" within cash flows from financing activities in the Company's condensed consolidated statement of cash flows for the six months ended June 30, 2017 .

Accounting Standards

Accounting Standards	6 Months Ended
	Jun. 29, 2018
Accounting Changes and Error Corrections [Abstract]
Accounting Standards	Note 2–Accounting Standards Accounting Standards Updates Adopted ASU 2014-09, Revenue from Contracts with Customers (Topic 606) In May 2014, the Financial Accounting Standards Board ("FASB") issued ASU 2014-09 ("ASC 606") and related amendments, which superseded all prior revenue recognition methods and industry-specific guidance. The core principle of ASC 606 is an entity should recognize revenue to depict the transfer of control for promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In applying the revenue principles, an entity is required to identify the contract(s) with a customer, identify the performance obligations, determine the transaction price, allocate the transaction price to the performance obligations and recognize revenue when the performance obligation is satisfied (i.e., either over time or point in time). ASC 606 further requires that companies disclose sufficient information to enable users of financial statements to understand the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. ASC 606 provided companies an option of two transition methods, the full retrospective method, in which case the standard would be applied to each prior reporting period presented and the cumulative effect of applying the standard would be recognized at the earliest period shown, or the modified retrospective method, in which case the cumulative effect of applying the standard would be recognized at the date of initial application. The ASU was effective for annual reporting periods beginning after December 15, 2017. Effective December 30, 2017 (the beginning of fiscal 2018), the Company adopted the requirements of ASC 606 using the modified retrospective method. The guidance was not applied to contracts that were complete at December 30, 2017, and the comparative information for the prior fiscal year has not been retrospectively adjusted. The adoption of ASC 606 did not have a material impact on the Company's condensed consolidated financial statements. The Company recorded a $1 million decrease to its beginning accumulated deficit as the cumulative impact of adoption of the new revenue standard. The primary impact was on certain units-of-delivery contracts, which the Company previously recognized revenue at a point in time when the customer accepted delivery of the product or service. Under ASC 606, revenues on certain units-of-delivery contracts are now recognized using an over-time model. The adoption of ASC 606 did not have a significant impact on the Company's revenue recognition policy as revenues on the substantially all of the Company's contracts continue to be recognized over time. In adopting ASC 606, the Company elected to use certain practical expedients permitted by the standard including using the portfolio approach where contracts with similar characteristics were assessed collectively to evaluate risk over the impact of ASC 606. The Company also elected to adopt the right-to-invoice practical expedient on certain cost-reimbursable contracts where the Company recognizes revenues as it is contractually able to invoice the customer based on the control transferred to the customer. ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedge Activities In August 2017, the FASB issued ASU 2017-12, which simplifies the application of hedge accounting and improves the financial reporting of hedging relationships to better portray the economic results of an entity's risk management activities. The ASU is effective for public companies for annual reporting periods beginning after December 15, 2018, and should be applied on a modified retrospective basis. Early adoption is permitted. The Company early adopted the provisions of ASU 2017-12 using the modified retrospective method during the quarter ended March 30, 2018, and recorded a $3 million increase to accumulated other comprehensive income and a corresponding increase to beginning accumulated deficit for the cumulative ineffectiveness gains related to the cash flow hedges. ASU 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income In February 2018, the FASB issued ASU 2018-02, which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act ("Tax Act"). This ASU is effective for all entities for annual reporting periods beginning after December 15, 2018, and should be applied either in the period of adoption or retrospectively to each period in which the effect of the change in the U.S. federal corporate income tax rate due to the Tax Act is recognized. Early adoption is permitted. The Company early adopted the provisions of ASU 2018-02 during the quarter ended March 30, 2018 (applied in the period of adoption), and recorded a $6 million increase to accumulated other comprehensive income and a corresponding increase to beginning accumulated deficit to reflect the changes in the U.S. federal corporate income tax rate as a result of the Tax Act. As a result of the adoption of ASU 2018-02, the Company's policy to release income tax effects in accumulated other comprehensive income is consistent with the underlying book method. The cumulative effect of the changes made to the Company's condensed consolidated balance sheet for the adoptions of the ASUs above was as follows: Balance at December 29, 2017 Adjustments due to ASU 2014-09 Adjustments due to ASU 2017-12 Adjustments due to ASU 2018-02 Balance at December 30, 2017 (in millions) Assets: Receivables, net $ 1,831 $ 4 $ — $ — $ 1,835 Inventory, prepaid expenses and other current assets 453 (3 ) — — 450 Equity: Accumulated deficit $ (7 ) $ 1 $ (3 ) $ (6 ) $ (15 ) Accumulated other comprehensive income 33 — 3 6 42 Accounting Standards Updates Issued But Not Yet Adopted ASU 2016-02 and ASU 2018-10, Leases (Topic 842) In February 2016, the FASB issued ASU 2016-02, which supersedes the current lease guidance under Leases (Topic 840) and makes several changes, such as requiring an entity to recognize a right-of-use asset and corresponding lease obligation on the balance sheet, classified as financing or operating, as appropriate. The update is effective for public companies for annual and interim reporting periods beginning after December 15, 2018, and should be adopted under the modified retrospective approach. The Company plans to adopt the new lease accounting standard in fiscal 2019 and is currently in the process of reviewing lease contracts, implementing a new lease accounting and administration software solution, establishing new processes and internal controls and evaluating the impact of certain accounting policy elections. The potential impact on the consolidated financial statements will largely be based on the present value of future minimum lease payments, the amount of which will depend upon the population of leases in effect at the date of adoption. In July 2018, the FASB issued ASU 2018-10, Codification Improvements to Topic 842, Leases, to add clarity to certain areas within ASU 2016-02. The effective date and transition requirements will be the same as ASU 2016-02. The Company will evaluate and adopt this ASU in conjunction with ASU 2016-02.

Significant Accounting Policies

Significant Accounting Policies	6 Months Ended
	Jun. 29, 2018
Accounting Policies [Abstract]
Significant Accounting Policies	Note 3–Significant Accounting Policies Revenue Recognition The Company's revenues from contracts with customers are from offerings including cybersecurity; data analytics; enterprise IT modernization; operations and logistics; sensors, collection and phenomenology; software development; and systems engineering , primarily with the U.S. government and its agencies. The Company also serves various state and local governments, foreign governments and U.S. commercial customers. The Company performs under various types of contracts, which include firm-fixed-price ("FFP"), time-and-materials ("T&M"), fixed-price-level-of-effort ("FP-LOE"), cost-plus-fixed-fee, cost-plus-award-fee, cost-plus-incentive-fee and fixed-price-incentive-fee ("FP-IF") contracts. To determine the proper revenue recognition, the Company first evaluates whether it has a duly approved and enforceable contract with a customer, in which the rights of the parties and payment terms are identified, and collectability is probable. The Company also evaluates whether two or more contracts should be combined and accounted for as a single contract, including the task orders issued under an indefinite delivery/indefinite quantity ("IDIQ") award. In addition, the Company assesses contract modifications to determine whether changes to existing contracts should be accounted for as part of the original contract or as a separate contract. Contract modifications for the Company generally relate to changes in contract specifications and requirements and do not add distinct services, and therefore are accounted for as part of the original contract. If contract modifications add distinct goods or services and increase the contract value by an amount that reflects the standalone selling price, those modifications are accounted for as separate contracts. Most of the Company's contracts comprise multiple promises including the design and build of software-based systems, integration of hardware and software solutions, running and maintaining of IT infrastructure and procurement services. In all cases, the Company assesses if the multiple promises should be accounted for as separate performance obligations or combined into a single performance obligation. The Company generally separates multiple promises in a contract as separate performance obligations if those promises are distinct, both individually and in the context of the contract. If multiple promises in a contract are highly interrelated or comprise a series of distinct services performed over time, they are combined and accounted for as a single performance obligation. The Company's contracts with the U.S. government often contain options to renew existing contracts for an additional period of time (generally a year at a time) under the same terms and conditions as the original contract, and generally do not provide the customer any material rights under the contract. The Company accounts for renewal options as separate contracts when they include distinct goods or services at standalone selling prices. Contracts with the U.S. government are subject to the Federal Acquisition Regulation ("FAR") and priced on estimated or actual costs of providing the goods or services. The FAR provides guidance on types of costs that are allowable in establishing prices for goods and services provided to the U.S. government and its agencies. Each contract is competitively priced and bid separately. Pricing for non-U.S. government agencies and commercial customers is based on specific negotiations with each customer. The Company excludes any taxes collected or imposed when determining the transaction price. Certain of the Company's cost-plus and fixed-price contracts contain award fees, incentive fees or other provisions that may either increase or decrease the transaction price. These variable amounts generally are awarded upon achievement of certain performance metrics, program milestones or cost targets and can be based upon customer discretion. The Company estimates variable consideration at the most probable amount that it expects to be entitled to, based on the assessment of the contractual variable fee criteria, complexity of work and related risks, extent of customer discretion, amount of variable consideration received historically and the potential of significant reversal of revenue. The Company allocates the transaction price of a contract to its performance obligations in the proportion of its respective standalone selling prices. The standalone selling price of the Company's performance obligations is generally based on an expected cost-plus margin approach, in accordance with the FAR. For certain product sales, the Company uses prices from other standalone sales. Substantially all of the Company's contracts do not contain a significant financing component, which would require an adjustment to the transaction price of the contract. The Company recognizes revenue on its service based contracts primarily over time as there is continuous transfer of control to the customer over the duration of the contract as the Company performs the promised services. For U.S. government contracts, continuous transfer of control to the customer is evidenced by clauses in the contract that allow the customer to unilaterally terminate the contract for convenience, pay for costs incurred plus a reasonable profit and take control of any work-in-process. Similarly, for non-U.S. government contracts, the customer typically controls the work-in-process as evidenced by rights to payment for work performed to date plus a reasonable profit to deliver products or services that do not have an alternate use to the Company. Anticipated losses on service based contracts are recognized as incurred. In certain product sales, where the products have an alternate use, the Company recognizes revenue at a point in time when the customer takes control of the asset usually denoted by possession and legal title. On FFP contracts, revenue recognized over time generally uses a method that measures the extent of progress towards completion of a performance obligation, principally using a cost-input method (referred to as the cost-to-cost method). Under the cost-to-cost method, revenue is recognized based on the proportion of total cost incurred to estimated total costs-at-completion ("EAC"). A performance obligation's EAC includes all direct costs such as materials, labor, subcontract costs, overhead, and a ratable portion of general and administrative costs. In addition, the Company includes in an EAC of a performance obligation future losses estimated to be incurred on onerous contracts, as and when known, and the most likely amount of transaction price (revenue) that the Company expects to receive for unpriced change orders (modifications). On certain other contracts, principally T&M, FP-LOE, and cost-plus, revenue is recognized using the right-to-invoice practical expedient as the Company is contractually able to invoice the customer based on the control transferred to the customer. Additionally, on maintenance (generally FFP) performance obligations, revenue is recognized over time using a straight-line method as the control of the services is provided to the customer evenly over the period of performance. For certain performance obligations, the Company is not primarily responsible for fulfilling the promise to provide the goods or service to the customer, does not have inventory risk and does not have discretion in establishing the price for the goods or service. In such cases, the Company recognizes revenue on a net basis. Contract costs generally include direct costs such as materials, labor, subcontract costs, and indirect costs identifiable with or allocable to a specific contract. Costs are expensed as incurred except for costs incurred during the transition phase of a new contract, which are capitalized and amortized on a straight-line basis over the expected life of that contract. The Company does not incur significant incremental costs to acquire contracts. Contract costs incurred for U.S. government contracts, including indirect costs, are subject to audit and adjustment by the Defense Contract Audit Agency ("DCAA") (see " Note 20–Contingencies "). Changes in Estimates on Contracts Changes in estimates related to contracts accounted for using the cost-to-cost method of accounting are recognized in the period in which such changes are made for the inception-to-date effect of the changes, with the exception of contracts acquired through the acquisition of Lockheed Martin's Information Systems & Global Solutions business ("IS&GS Business") (see " Note 6–Acquisitions "), where the adjustment is made for the period commencing from the date of acquisition. Changes in estimates on contracts for the periods presented were as follows: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions, except per share amounts) Net favorable impact to income before income taxes $ 34 $ 40 $ 69 $ 62 Impact on diluted EPS attributable to Leidos common stockholders $ 0.17 $ 0.17 $ 0.34 $ 0.26 The impact on diluted EPS attributable to Leidos common stockholders is calculated using the Company's statutory tax rate. During the quarter and six months ended June 29, 2018 , revenue recognized from performance obligations satisfied in previous periods was $32 million and $66 million , respectively. The changes in estimates primarily relate to revisions of variable consideration, including award fees, and revisions to estimates at completion resulting from changes in contract scope, mitigation of contract risks or due to true-ups of contract estimates at the end of contract performance. Cash and Cash Equivalents The Company's cash equivalents are primarily comprised of investments in several large institutional money market funds and bank deposits, with original maturity of three months or less. The Company includes outstanding payments within "Cash and cash equivalents" and correspondingly increases "Accounts payable and accrued liabilities" on the condensed consolidated balance sheets. At June 29, 2018 , and December 29, 2017, the Company included $63 million and $169 million , respectively, of outstanding payments within "Cash and cash equivalents." Receivables The Company's receivables include amounts billed and currently due from customers, amounts billable where the right to consideration is unconditional and amounts unbilled. Amounts billable and unbilled amounts are recognized at estimated realizable value and consist of costs and fees, substantially all of which are expected to be billed and collected generally within one year. Unbilled amounts also include rate variances that are billable upon negotiation of final indirect rates with the DCAA. The typical billing for the Company's cost-reimbursable and T&M contracts is as costs are incurred. FFP contracts are billed either based on milestones, which are the achievement of specific events as defined in the contract, or based on progress payments, which are interim payments up to a designated amount of costs incurred as work progresses. On certain contracts, the customer withholds a certain percentage of the contract price (retainage). These withheld amounts are included within the Company's unbilled receivables and are billed upon contract completion or the occurrence of a specified event, and when negotiation of final indirect rates with the U.S. government is complete. Based on the Company's historical experience, the write-offs of retention balances have not been significant. When events or conditions indicate that amounts outstanding from customers may become uncollectible, an allowance is estimated and recorded. Amounts billed and collected on contracts but not yet recorded as revenue because the Company has not performed its obligation under the arrangement with a customer are deferred and included within "Accounts payable and accrued liabilities" or "Other long-term liabilities" on the condensed consolidated balance sheets.

Revenues

Revenues	6 Months Ended
	Jun. 29, 2018
Revenue from Contract with Customer [Abstract]
Revenues	Note 4–Revenues Dual Reporting The effects to the condensed consolidated financial statements at June 29, 2018 , as a result of applying ASC 606, rather than previous GAAP ("ASC 605"), were the following: Balance Sheet As Reported (ASC 606) As Adjusted (ASC 605) (in millions) Receivables, net $ 1,779 $ 1,775 Inventory, prepaid expenses and other current assets 458 461 Accumulated earnings (deficit) 133 132 Income Statement Three Months Ended June 29, 2018 Six Months Ended June 29, 2018 As Reported (ASC 606) As Adjusted As Reported (ASC 606) As Adjusted (in millions) Revenues $ 2,529 $ 2,530 $ 4,972 $ 4,968 Cost of revenues 2,152 2,152 4,238 4,235 Operating income 199 200 358 357 The changes reflected above were primarily due to the Company's units-of-delivery contracts, which were recognized at a point in time under ASC 605 and are recognized using an over-time model under ASC 606. Remaining Performance Obligations Remaining performance obligations represent the expected value of exercised contracts, both funded and unfunded, less revenue recognized to date. Remaining performance obligations do not include unexercised option periods and future potential task orders expected to be awarded under IDIQ contracts. As of June 29, 2018 , the Company had $9.0 billion of remaining performance obligations, which are expected to be recognized as revenue in the amounts of $4.6 billion , $2.0 billion and $2.4 billion for the remainder of fiscal 2018, fiscal 2019 and fiscal 2020 and thereafter, respectively. Disaggregation of Revenues The Company disaggregates revenues by customer-type, contract-type and geographic location for each of its reportable segments. These categories represent how the nature, timing and uncertainty of revenues and cash flows are affected by the U.S. government procurement environment. Disaggregated revenues by customer-type were as follows: Three Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) DoD $ 1,099 $ 26 $ 82 $ 1,207 Other government agencies (1) 50 574 327 951 Commercial and non-U.S. customers 107 222 42 371 Total $ 1,256 $ 822 $ 451 $ 2,529 Six Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) DoD $ 2,131 $ 49 $ 174 $ 2,354 Other government agencies (1) 95 1,163 625 1,883 Commercial and non-U.S. customers 208 450 77 735 Total $ 2,434 $ 1,662 $ 876 $ 4,972 (1) Includes non-DoD federal government agencies, state and local government agencies. The majority of the Company's revenues is generated from U.S. government contracts, either as a prime contractor or as a subcontractor to other contractors. Revenues from the U.S. government can be adversely impacted by spending caps or changes in budgetary priorities of the U.S. government, as well as delays in program start dates or the award of a contract. Government spending levels for the DoD may be impacted by spending priorities as a result of competing demands for federal funds. Disaggregated revenues by contract-type were as follows: Three Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) Cost-reimbursement and fixed price-incentive fee $ 860 $ 475 $ 42 $ 1,377 Firm-fixed-price 259 203 284 746 Time and materials and fixed-price-level-of-effort 137 144 125 406 Total $ 1,256 $ 822 $ 451 $ 2,529 Six Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) Cost-reimbursement and fixed price-incentive fee $ 1,631 $ 914 $ 92 $ 2,637 Firm-fixed-price 542 459 537 1,538 Time and materials and fixed-price-level-of-effort 261 289 247 797 Total $ 2,434 $ 1,662 $ 876 $ 4,972 Cost-reimbursement and FP-IF contracts are generally lower risk and have lower profits. T&M and FP-LOE contracts are also low risk but profits may vary depending on actual labor costs compared to negotiated contract billing rates. FFP contracts offer the potential for higher profits while increasing the Company’s exposure to risk of cost overruns. Disaggregated revenues by geographic location were as follows: Three Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) United States $ 1,164 $ 693 $ 451 $ 2,308 International 92 129 — 221 Total $ 1,256 $ 822 $ 451 $ 2,529 Six Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) United States $ 2,252 $ 1,389 $ 876 $ 4,517 International 182 273 — 455 Total $ 2,434 $ 1,662 $ 876 $ 4,972 The Company's international business operations are subject to additional and different risks than its U.S. business. Failure to comply with U.S government laws and regulations applicable to international business, such as the Foreign Corrupt Practices Act or U.S. export control regulations, could have an adverse impact on the Company's business with the U.S. government. In some countries, there is an increased chance for economic, legal or political changes that may adversely affect the performance of the Company's services, sales of products or repatriation of profits. International transactions can also involve increased financial and legal risks arising from foreign exchange variability, imposition of tariffs or additional taxes and restrictive trade policies, and delays or failure to collect amounts due to differing legal systems. Note 5–Contract Assets and Liabilities Contract assets include unbilled receivables, which is the amount of revenue recognized that exceeds the amount billed to the customer, where right to payment is not just subject to the passage of time. Contract assets also include transition costs and project assets. Transition costs represent costs that are incurred under certain service based contracts, usually at the beginning of the contract performance, to transition the services, employees and equipment from the customer. Project assets represent assets for specific contracts. Contract liabilities consist of deferred revenue. The components of contract assets and contract liabilities consisted of the following: Balance sheet line item June 29, December 30, 2017 (1) (in millions) Contract assets - current: Unbilled receivables (2) Receivables, net $ 734 $ 844 Transition costs and project assets Inventory, prepaid expenses and other current assets 83 59 $ 817 $ 903 Contract assets - non-current: Transition costs and project assets Other assets $ 11 $ 13 Contract liabilities - current: Deferred revenue Accounts payable and accrued liabilities $ 311 $ 293 Contract liabilities - non-current: Deferred revenue Other long-term liabilities $ 12 $ 17 (1) Includes the cumulative effect of the changes made to the Company's opening balance sheet at December 30, 2017, as a result of the adoption of ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . (2) Balances exclude $434 million and $234 million determined to be billable at June 29, 2018 , and December 30, 2017, respectively. The decrease in unbilled receivables was primarily due to the timing of billings and revenue recognized on certain contracts. The increase in transition costs and project assets was primarily due to purchases on certain contracts partially offset by amortization. The increase in deferred revenue was primarily due to increased advance payments from customers. During the quarter and six months ended June 29, 2018 , the Company recognized revenue of $72 million and $127 million , respectively, relating to amounts that were included as a contract liability at December 30, 2017 . During the quarter and six months ended June 29, 2018 , the Company recognized $37 million and $40 million of amortization, respectively, related to its transition costs and project assets. The Company did not recognize any impairment losses on contract assets for the quarter and six months ended June 29, 2018 .

Contract Asset and Liabilities

Contract Asset and Liabilities	6 Months Ended
	Jun. 29, 2018
Revenue from Contract with Customer [Abstract]
Contract Asset and Liabilities	Note 4–Revenues Dual Reporting The effects to the condensed consolidated financial statements at June 29, 2018 , as a result of applying ASC 606, rather than previous GAAP ("ASC 605"), were the following: Balance Sheet As Reported (ASC 606) As Adjusted (ASC 605) (in millions) Receivables, net $ 1,779 $ 1,775 Inventory, prepaid expenses and other current assets 458 461 Accumulated earnings (deficit) 133 132 Income Statement Three Months Ended June 29, 2018 Six Months Ended June 29, 2018 As Reported (ASC 606) As Adjusted As Reported (ASC 606) As Adjusted (in millions) Revenues $ 2,529 $ 2,530 $ 4,972 $ 4,968 Cost of revenues 2,152 2,152 4,238 4,235 Operating income 199 200 358 357 The changes reflected above were primarily due to the Company's units-of-delivery contracts, which were recognized at a point in time under ASC 605 and are recognized using an over-time model under ASC 606. Remaining Performance Obligations Remaining performance obligations represent the expected value of exercised contracts, both funded and unfunded, less revenue recognized to date. Remaining performance obligations do not include unexercised option periods and future potential task orders expected to be awarded under IDIQ contracts. As of June 29, 2018 , the Company had $9.0 billion of remaining performance obligations, which are expected to be recognized as revenue in the amounts of $4.6 billion , $2.0 billion and $2.4 billion for the remainder of fiscal 2018, fiscal 2019 and fiscal 2020 and thereafter, respectively. Disaggregation of Revenues The Company disaggregates revenues by customer-type, contract-type and geographic location for each of its reportable segments. These categories represent how the nature, timing and uncertainty of revenues and cash flows are affected by the U.S. government procurement environment. Disaggregated revenues by customer-type were as follows: Three Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) DoD $ 1,099 $ 26 $ 82 $ 1,207 Other government agencies (1) 50 574 327 951 Commercial and non-U.S. customers 107 222 42 371 Total $ 1,256 $ 822 $ 451 $ 2,529 Six Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) DoD $ 2,131 $ 49 $ 174 $ 2,354 Other government agencies (1) 95 1,163 625 1,883 Commercial and non-U.S. customers 208 450 77 735 Total $ 2,434 $ 1,662 $ 876 $ 4,972 (1) Includes non-DoD federal government agencies, state and local government agencies. The majority of the Company's revenues is generated from U.S. government contracts, either as a prime contractor or as a subcontractor to other contractors. Revenues from the U.S. government can be adversely impacted by spending caps or changes in budgetary priorities of the U.S. government, as well as delays in program start dates or the award of a contract. Government spending levels for the DoD may be impacted by spending priorities as a result of competing demands for federal funds. Disaggregated revenues by contract-type were as follows: Three Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) Cost-reimbursement and fixed price-incentive fee $ 860 $ 475 $ 42 $ 1,377 Firm-fixed-price 259 203 284 746 Time and materials and fixed-price-level-of-effort 137 144 125 406 Total $ 1,256 $ 822 $ 451 $ 2,529 Six Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) Cost-reimbursement and fixed price-incentive fee $ 1,631 $ 914 $ 92 $ 2,637 Firm-fixed-price 542 459 537 1,538 Time and materials and fixed-price-level-of-effort 261 289 247 797 Total $ 2,434 $ 1,662 $ 876 $ 4,972 Cost-reimbursement and FP-IF contracts are generally lower risk and have lower profits. T&M and FP-LOE contracts are also low risk but profits may vary depending on actual labor costs compared to negotiated contract billing rates. FFP contracts offer the potential for higher profits while increasing the Company’s exposure to risk of cost overruns. Disaggregated revenues by geographic location were as follows: Three Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) United States $ 1,164 $ 693 $ 451 $ 2,308 International 92 129 — 221 Total $ 1,256 $ 822 $ 451 $ 2,529 Six Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) United States $ 2,252 $ 1,389 $ 876 $ 4,517 International 182 273 — 455 Total $ 2,434 $ 1,662 $ 876 $ 4,972 The Company's international business operations are subject to additional and different risks than its U.S. business. Failure to comply with U.S government laws and regulations applicable to international business, such as the Foreign Corrupt Practices Act or U.S. export control regulations, could have an adverse impact on the Company's business with the U.S. government. In some countries, there is an increased chance for economic, legal or political changes that may adversely affect the performance of the Company's services, sales of products or repatriation of profits. International transactions can also involve increased financial and legal risks arising from foreign exchange variability, imposition of tariffs or additional taxes and restrictive trade policies, and delays or failure to collect amounts due to differing legal systems. Note 5–Contract Assets and Liabilities Contract assets include unbilled receivables, which is the amount of revenue recognized that exceeds the amount billed to the customer, where right to payment is not just subject to the passage of time. Contract assets also include transition costs and project assets. Transition costs represent costs that are incurred under certain service based contracts, usually at the beginning of the contract performance, to transition the services, employees and equipment from the customer. Project assets represent assets for specific contracts. Contract liabilities consist of deferred revenue. The components of contract assets and contract liabilities consisted of the following: Balance sheet line item June 29, December 30, 2017 (1) (in millions) Contract assets - current: Unbilled receivables (2) Receivables, net $ 734 $ 844 Transition costs and project assets Inventory, prepaid expenses and other current assets 83 59 $ 817 $ 903 Contract assets - non-current: Transition costs and project assets Other assets $ 11 $ 13 Contract liabilities - current: Deferred revenue Accounts payable and accrued liabilities $ 311 $ 293 Contract liabilities - non-current: Deferred revenue Other long-term liabilities $ 12 $ 17 (1) Includes the cumulative effect of the changes made to the Company's opening balance sheet at December 30, 2017, as a result of the adoption of ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . (2) Balances exclude $434 million and $234 million determined to be billable at June 29, 2018 , and December 30, 2017, respectively. The decrease in unbilled receivables was primarily due to the timing of billings and revenue recognized on certain contracts. The increase in transition costs and project assets was primarily due to purchases on certain contracts partially offset by amortization. The increase in deferred revenue was primarily due to increased advance payments from customers. During the quarter and six months ended June 29, 2018 , the Company recognized revenue of $72 million and $127 million , respectively, relating to amounts that were included as a contract liability at December 30, 2017 . During the quarter and six months ended June 29, 2018 , the Company recognized $37 million and $40 million of amortization, respectively, related to its transition costs and project assets. The Company did not recognize any impairment losses on contract assets for the quarter and six months ended June 29, 2018 .

Acquisitions

Acquisitions	6 Months Ended
	Jun. 29, 2018
Business Combinations [Abstract]
Acquisitions	Note 6–Acquisitions On August 16, 2016, a wholly-owned subsidiary of Leidos Holdings, Inc. merged with the IS&GS Business in a Reverse Morris Trust transaction. The acquired IS&GS Business was renamed Leidos Innovations Corporation. On January 10, 2018, the final amount of the net working capital of the IS&GS Business was determined through a binding arbitration proceeding in accordance with the Separation Agreement with Lockheed Martin. On January 18, 2018, the final working capital amount of $105 million was paid to Lockheed Martin, of which $24 million and $81 million was presented as cash flows from operating and investing activities, respectively, in the Company's condensed consolidated statement of cash flows. During the quarter ended June 29, 2018, a tax indemnification liability of $23 million was paid to Lockheed Martin in accordance with the Tax Matters Agreement, which was presented as cash flows from financing activities in the Company's condensed consolidated statement of cash flows. The Company incurred the following expenses related to the acquisition and integration of the IS&GS Business: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Acquisition costs $ — $ — $ — $ 1 Integration costs (1) 7 16 22 34 Total acquisition and integration costs $ 7 $ 16 $ 22 $ 35 (1) For the quarter and six months ended June 29, 2018 , the Company reclassified $4 million from restructuring expenses to integration costs. These acquisition and integration costs have been recorded within Corporate and presented in "Integration and restructuring costs" on the condensed consolidated statements of income.

Divestitures

Divestitures	6 Months Ended
	Jun. 29, 2018
Discontinued Operations and Disposal Groups [Abstract]
Divestitures	Note 7–Divestitures Commercial Cybersecurity Business On June 5, 2018, Leidos entered into a Stock and Asset Purchase Agreement to sell the Company's commercial cybersecurity business, included within the Company's Civil segment, in order to focus on providing solutions, including cybersecurity, to the Company's core markets of governments and highly regulated industries. The sale is expected to be completed during the second half of fiscal 2018 and is not expected to result in a loss. The Company has presented the associated assets and liabilities of the business as held for sale in the Company's condensed consolidated balance sheet as of June 29, 2018 . The major classes of assets and liabilities classified as held for sale were as follows: June 29, (in millions) Receivables, net $ 21 Inventory, prepaid expenses and other current assets 3 Property, plant and equipment, net 3 Intangible assets, net 5 Goodwill 57 Deferred tax assets 10 Total assets held for sale $ 99 Accounts payable and accrued liabilities $ 12 Accrued payroll and employee benefits 5 Other long-term liabilities 5 Total liabilities held for sale $ 22 The planned disposition does not represent a strategic shift in operations that will have a material effect on the Company's operations and financial results, and accordingly was not presented as discontinued operations. Plainfield Renewable Energy Holdings LLC On July 24, 2015, the Company completed the sale of its equity interests in Plainfield Renewable Energy Holdings LLC ("Plainfield") for an aggregate consideration of $102 million , subject to certain adjustments and contingent earn-out payments. The consideration received by the Company at closing consisted of a cash payment of $29 million and a secured promissory note for $73 million , net of discount (the "Note"). The Note is payable semi-annually with a final lump sum due in July 2018 . The Company collected $6 million of principal and interest during the quarter ended March 31, 2017. During the quarter ended June 30, 2017, Plainfield exercised the first of three one -year term extension options available under the original credit agreement, thereby extending the maturity date of the Note to July 24, 2018. Concurrent with this extension, the interest rate on the Note increased from 6% to 8% . Also, during the quarter ended June 30, 2017, Leidos and Plainfield entered into an amendment to the Note allowing Plainfield to defer up to $4 million of the interest and principal payments due in July 2017 and January 2018 until July 2018. In consideration of this deferment, Leidos received certain concessions and releases from obligations under the original transaction documents. In January 2018, the Company entered into negotiations with the equity owners of Plainfield regarding the Plainfield Recapitalization Plan ("Plan"). The proposed Plan envisions raising new equity combined with reduction of Plainfield's debt. The net realizable value of the Note, at December 29, 2017, was estimated to be approximately $40 million , compared to its carrying value of $73 million , including accrued interest. As a result, the Company recorded a $33 million impairment of its Note during the quarter ended December 29, 2017, which was presented within " Other income, net " in the Company's condensed consolidated statement of income. In June 2018, Leidos and Plainfield entered into an additional amendment to the Note, allowing Plainfield to defer the maturity of the Note until the earlier of July 13, 2018, or the date Plainfield successfully closes on a refinancing agreement with a third party. Under the terms of the agreement, if Plainfield successfully refinances the Note prior to July 13, 2018, Leidos shall allow Plainfield to settle the Note in full for $40 million plus 50% of additional net proceeds obtained by Plainfield. See " Note 22–Subsequent Events " regarding the additional amendment entered into in July 2018. As of June 29, 2018, the Company continues to expect the Note to be collectible in full.

Restructuring Expenses

Restructuring Expenses	6 Months Ended
	Jun. 29, 2018
Restructuring and Related Activities [Abstract]
Restructuring Expenses	Note 8–Restructuring Expenses After the acquisition of the IS&GS Business, the Company began an initiative to reduce its cost structure, which includes optimization of its real estate portfolio by vacating certain facilities and consolidating others, and by reducing headcount. The restructuring expenses related to this program were as follows: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Severance costs $ — $ 2 $ 1 $ 12 Lease termination expenses (1) 1 4 2 7 Restructuring expenses related to the IS&GS Business $ 1 $ 6 $ 3 $ 19 (1) For the quarter and six months ended June 29, 2018 , the Company reclassified $4 million from restructuring expenses to integration costs. As of June 29, 2018 , Leidos has recognized a total of $52 million of expense in connection with these restructuring activities. These restructuring expenses have been recorded within Corporate and presented in "Integration and restructuring costs" on the condensed consolidated statements of income. The restructuring liability related to this program was as follows: Severance Costs Lease Termination Expenses Total (in millions) Balance as of December 30, 2016 $ 7 $ 1 $ 8 Charges 18 19 37 Cash payments (20 ) (16 ) (36 ) Balance as of December 29, 2017 5 4 9 Charges (1) 1 2 3 Cash payments (2) (6 ) (2 ) (8 ) Balance as of June 29, 2018 $ — $ 4 $ 4 (1) Includes a reclassification of $4 million from restructuring to integration. (2) Includes a reclassification for payments of $3 million from restructuring to integration.

Goodwill

Goodwill	6 Months Ended
	Jun. 29, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	Note 9–Goodwill The following table presents changes in the carrying amount of goodwill by reportable segment: Defense Solutions Civil Health Total (in millions) Goodwill at December 30, 2016 $ 1,954 $ 1,731 $ 937 $ 4,622 Adjustment to original purchase price allocation 94 259 (16 ) 337 Foreign currency translation adjustments 7 8 — 15 Goodwill at December 29, 2017 2,055 1,998 921 4,974 Foreign currency translation adjustments (25 ) (5 ) — (30 ) Transfers to assets held for sale — (57 ) — (57 ) Goodwill at June 29, 2018 $ 2,030 $ 1,936 $ 921 $ 4,887 Accumulated goodwill impairment losses were $369 million and $117 million within the Health and Civil segments, respectively, at June 29, 2018 , December 29, 2017, and December 30, 2016. Goodwill is tested for impairment at the beginning of the fourth quarter and during interim periods whenever events or circumstances indicate that the carrying value may not be recoverable. There were no goodwill impairments during the six months ended June 29, 2018 , and June 30, 2017 .

Intangible Assets

Intangible Assets	6 Months Ended
	Jun. 29, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Note 10–Intangible Assets Intangible assets consisted of the following: June 29, 2018 December 29, 2017 Gross carrying value Accumulated amortization Net carrying value Gross carrying value Accumulated amortization Net carrying value (in millions) Finite-lived intangible assets: Program and contract intangibles $ 1,005 $ (281 ) $ 724 $ 1,013 $ (187 ) $ 826 Software and technology 89 (68 ) 21 89 (64 ) 25 Customer relationships 4 (4 ) — 4 (3 ) 1 Backlog — — — 158 (158 ) — Total finite-lived intangible assets 1,098 (353 ) 745 1,264 (412 ) 852 Indefinite-lived intangible assets: Trade names 4 — 4 4 — 4 Total intangible assets $ 1,102 $ (353 ) $ 749 $ 1,268 $ (412 ) $ 856 Amortization expense was $51 million and $101 million for the quarter and six months ended June 29, 2018 , respectively, and $67 million and $136 million for the quarter and six months ended June 30, 2017 , respectively. Program and contract intangible assets are amortized over their respective estimated useful lives in proportion to the pattern of economic benefit based on expected future discounted cash flows. Customer relationships and backlog intangible assets are amortized on a straight-line basis over their estimated useful lives. Software and technology intangible assets are amortized either on a straight-line basis over their estimated useful lives or over their respective estimated useful lives in proportion to the pattern of economic benefit based on expected future discounted cash flows, as deemed appropriate. The estimated annual amortization expense as of June 29, 2018 , was as follows: Fiscal Year Ending (in millions) 2018 (remainder of year) $ 100 2019 170 2020 126 2021 105 2022 92 2023 and thereafter 152 $ 745

Property, Plant and Equipment

Property, Plant and Equipment	6 Months Ended
	Jun. 29, 2018
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Note 11–Property, Plant and Equipment Property, plant and equipment, net consisted of the following: June 29, December 29, (in millions) Computers and other equipment $ 188 $ 194 Leasehold improvements 186 171 Buildings and improvements 56 54 Office furniture and fixtures 35 34 Construction in progress 45 44 Land 40 49 550 546 Less: accumulated depreciation (329 ) (314 ) $ 221 $ 232 Depreciation expense was $15 million and $28 million for the quarter and six months ended June 29, 2018 , respectively, and $13 million and $26 million for the quarter and six months ended June 30, 2017 , respectively. During the quarter ended March 30, 2018, the Company determined that the carrying amount of a real estate property may not be recoverable and as a result recorded an impairment charge of $7 million , which was recorded within Corporate.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 29, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 12–Fair Value Measurements The accounting standard for fair value measurements establishes a three-level fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: observable inputs such as quoted prices in active markets (Level 1); inputs other than quoted prices in active markets for identical assets or liabilities that are observable either directly or indirectly or quoted prices that are not active (Level 2); and unobservable inputs in which there is little or no market data (e.g., discounted cash flow and other similar pricing models), which requires the Company to develop its own assumptions (Level 3). The accounting guidance for fair value measurements requires that the Company maximize the use of observable inputs and minimize the use of unobservable inputs in determining fair value. The accounting guidance provides for the irrevocable option to elect, on a contract-by-contract basis, to measure certain financial assets and liabilities at fair value at inception of the contract and record any subsequent changes in fair value in earnings. The Company has not made fair value option elections on any of its financial assets and liabilities. The Company's financial instruments measured at fair value on a recurring basis consisted of the following: June 29, 2018 December 29, 2017 Carrying value Fair value Carrying value Fair value (in millions) Financial assets: Derivatives $ 55 $ 55 $ 37 $ 37 Financial liabilities: Derivatives 7 7 — — The Company's derivatives consisted of the fair value interest rate swaps on its $450 million , fixed rate 4.45% senior secured notes maturing in December 2020 and cash flow interest rate swaps on $1.6 billion of the Company's variable rate senior secured term loans (see " Note 13–Derivative Instruments "). The fair value of the fair value interest rate swaps and cash flow interest rate swaps is determined based on observed values for underlying interest rates on the LIBOR yield curve and the underlying interest rate, respectively (Level 2 inputs). The carrying amounts of the Company's financial instruments, other than derivatives, which include cash equivalents, accounts receivable, accounts payable and accrued expenses, are reasonable estimates of their related fair values. The carrying value of the Company's notes receivable of $63 million as of June 29, 2018 , and December 29, 2017, approximates fair value as the stated interest rates within the agreements are consistent with the current market rates used in notes with similar terms in the market (Level 2 inputs). As of June 29, 2018 , and December 29, 2017, the fair value of debt was $3.1 billion and $3.2 billion , respectively, and the carrying amount was $3.1 billion at both dates (see " Note 14–Debt "). The fair value of long-term debt is determined based on current interest rates available for debt with terms and maturities similar to the Company’s existing debt arrangements (Level 2 inputs). At March 30, 2018, the Company had a real estate property measured at fair value (Level 2), which resulted in an impairment charge of $7 million (see " Note 11–Property, Plant and Equipment "). The Company did not have any assets or liabilities measured at fair value on a non-recurring basis at June 29, 2018 .

Derivative Instruments

Derivative Instruments	6 Months Ended
	Jun. 29, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Note 13–Derivative Instruments The Company manages its risk to changes in interest rates through the use of derivative instruments. The Company does not hold derivative instruments for trading or speculative purposes. For fixed rate borrowings, the Company uses variable interest rate swaps, effectively converting fixed rate borrowings to variable rate borrowings. These swaps are designated as fair value hedges. For variable rate borrowings, the Company uses fixed interest rate swaps, effectively converting a portion of the variable interest rate payments to fixed interest rate payments. These swaps are designated as cash flow hedges. The fair value of the Company's interest rate swaps was as follows: Asset Derivatives Balance sheet line item June 29, December 29, (in millions) Cash flow interest rate swaps Other assets $ 55 $ 37 Liability Derivatives Balance sheet line item June 29, December 29, (in millions) Fair value interest rate swaps Other long-term liabilities $ 7 $ — The cash flows associated with the interest rate swaps are classified as operating activities in the condensed consolidated statements of cash flows. Fair Value Hedges The Company has interest rate swap agreements to hedge the fair value of the $450 million fixed rate 4.45% senior secured notes maturing in December 2020 (the "Notes"). The objective of these instruments is to hedge the Notes against changes in fair value due to the variability in the six-month LIBOR rate (the benchmark interest rate). Under the terms of the interest rate swap agreements, the Company will receive semi-annual interest payments at the coupon rate of 4.45% and will pay variable interest based on the six-month LIBOR rate. The interest rate swaps were accounted for as a fair value hedge of the Notes and qualified for the shortcut method of hedge accounting, which allows for the assumption of no ineffectiveness reported in earnings. The resulting changes in the fair value of the interest rate swaps are fully offset by the changes in the fair value of the underlying debt (the hedged item) (See " Note 14–Debt "). The fair value of the Notes is stated at an amount that reflects changes in the six-month LIBOR rate subsequent to the inception of the interest rate swaps through the reporting date. The following amounts were recorded on the condensed consolidated balance sheets related to cumulative basis adjustments for fair value hedges: Carrying amount of hedged item Cumulative amount of fair value adjustment included within the hedged item Balance sheet line item of hedged item June 29, December 29, June 29, December 29, (in millions) Long-term debt, net of current portion $ 442 $ 449 $ (7 ) $ — Cash Flow Hedges The Company has interest rate swap agreements to hedge the cash flows of a portion of its variable rate senior secured term loans (the "Variable Rate Loans"). The objective of these instruments is to reduce variability in the forecasted interest payments of the Company's Variable Rate Loans, which are based on the LIBOR rate. Under the terms of the interest rate swap agreements, the Company will receive monthly variable interest payments based on the one-month LIBOR rate and will pay interest at a fixed rate. In February 2018, the Company entered into interest rate swap agreements to hedge the cash flows of an additional $250 million of its Variable Rate Loans. The interest rate swap agreements on $1.1 billion of the Company's Variable Rate Loans have a maturity date of December 2021 and a fixed interest rate of 1.08% . The interest rate swap agreements on $300 million and $250 million of the Company's Variable Rate Loans both have a maturity date of August 2022 and a fixed interest rate of 1.66% and 2.59% , respectively. The interest rate swap transactions were accounted for as cash flow hedges. The gain/loss on the swap is reported as a component of other comprehensive income/loss and is reclassified into earnings when the interest payments on the underlying hedged items impact earnings. As a result of the Company's adoption of ASU 2017-12 in the quarter ended March 30, 2018, a qualitative assessment of hedge effectiveness is performed on a quarterly basis, unless facts and circumstances indicate the hedge may no longer be highly effective. The effect of the Company's cash flow hedges on other comprehensive income and earnings for the periods presented was as follows: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Total interest expense, net presented in the condensed consolidated statements of income in which the effects of cash flow hedges are recorded $ 35 $ 34 $ 69 $ 70 Amount recognized in other comprehensive income 7 (4 ) 21 (3 ) Amount reclassified from accumulated other comprehensive income to interest expense, net (2 ) — (3 ) 1 The Company expects to reclassify gains of $15 million from accumulated other comprehensive income into earnings during the next 12 months.

Debt

Debt	6 Months Ended
	Jun. 29, 2018
Debt Disclosure [Abstract]
Debt	Note 14–Debt The Company's debt consisted of the following: Stated interest rate Effective interest rate June 29, 2018 (1) December 29, 2017 (1) (in millions) Senior secured notes: $450 million notes, due December 2020 4.45% 4.53% $ 442 $ 449 $300 million notes, due December 2040 5.95% 6.03% 216 216 Senior secured term loans: $690 million Term Loan A, due August 2022 3.88% 4.38% 625 644 $310 million Term Loan A, due August 2022 3.88% 4.37% 262 270 $1,131 million Term Loan B, due August 2023 3.88% 4.26% 1,091 1,101 Senior unsecured notes: $250 million notes, due July 2032 7.13% 7.43% 246 246 $300 million notes, due July 2033 5.50% 5.88% 158 158 Capital leases and notes payable due on various dates through fiscal 2022 0%-5.55% Various 21 27 Total long-term debt 3,061 3,111 Less: current portion 71 55 Total long-term debt, net of current portion $ 2,990 $ 3,056 (1) The carrying amounts of the senior secured term loans and notes and unsecured notes as of June 29, 2018 , and December 29, 2017 , include the remaining principal outstanding of $3,088 million and $3,129 million , respectively, less total unamortized debt discounts and deferred debt issuances costs of $41 million and $45 million , respectively, less $7 million related to the fair value interest rate swaps (see " Note 13–Derivative Instruments ") as of June 29, 2018 . In March 2018, Leidos amended the terms of its senior secured $1.1 billion Term Loan B, due August 2023. As a result, the margin on Term Loan B was reduced by 25 basis points to 1.75% . The repricing of the term loan became effective March 15, 2018. The interest rate on the Company's senior secured term loans is determined based on the LIBOR rate plus a margin. The margin for the Term Loan A loans ranges from 1.50% to 2.00% , depending on the Company's senior secured leverage ratio, and is computed on a quarterly basis. At June 29, 2018 , the current margin on Term Loan A and Term Loan B was 1.75% . The Company made required quarterly payments on its senior secured term loans of $16 million and $31 million during the quarter and six months ended June 29, 2018 , respectively, and $21 million and $41 million during the quarter and six months ended June 30, 2017 , respectively. In April 2018, the Company made a required debt prepayment of $10 million on its senior secured term loans. The prepayment was a result of the annual excess cash flow calculation clause in the Company's credit agreements. In addition to the required payments on its term loans, the Company prepaid $25 million during the quarter ended June 30, 2017. The Company has a revolving credit facility providing up to $750 million in secured borrowing capacity at interest rates determined based upon the LIBOR rate plus a margin that is subject to step-down provisions based on the Company's senior secured leverage ratio. The maturity date of this credit facility is August 2022 . As of June 29, 2018 , and December 29, 2017 , there were no borrowings outstanding under the credit facility. Amortization of the debt discount and deferred debt issuance costs related to the senior secured term loans and notes, unsecured notes and revolving credit facility was $3 million and $6 million for the quarter and six months ended June 29, 2018 , respectively, and $3 million and $7 million for the quarter and six months ended June 30, 2017 , respectively. The senior secured term loans and notes, unsecured notes and revolving credit facility are fully and unconditionally guaranteed and contain certain customary restrictive covenants, including among other things, restrictions on the Company's ability to create liens and enter into sale and leaseback transactions under certain circumstances. The Company was in compliance with all covenants as of June 29, 2018 .

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	6 Months Ended
	Jun. 29, 2018
Equity [Abstract]
Accumulated Other Comprehensive Income	Note 15–Accumulated Other Comprehensive Income Changes in the components of accumulated other comprehensive income were as follows: Foreign currency translation adjustments Unrecognized gain on derivative instruments Pension adjustments Total accumulated other comprehensive income (in millions) Balance at December 30, 2016 $ (7 ) $ 10 $ (7 ) $ (4 ) Other comprehensive income 36 10 9 55 Taxes (12 ) (6 ) — (18 ) Balance at December 29, 2017 17 14 2 33 Cumulative adjustments related to ASU adoptions (Note 2) 3 10 (4 ) 9 Balance at December 30, 2017 20 24 (2 ) 42 Other comprehensive (loss) income (38 ) 21 — (17 ) Taxes 5 (4 ) — 1 Reclassification from accumulated other comprehensive income — (3 ) — (3 ) Balance at June 29, 2018 $ (13 ) $ 38 $ (2 ) $ 23 Reclassifications from unrecognized gain on derivative instruments are recorded in "Interest expense, net" in the Company's condensed consolidated statements of income.

Earnings Per Share (EPS)

Earnings Per Share (EPS)	6 Months Ended
	Jun. 29, 2018
Earnings Per Share [Abstract]
Earnings Per Share (EPS)	Note 16–Earnings Per Share ("EPS") The following table provides a reconciliation of the weighted average number of shares outstanding used to compute basic and diluted EPS for the periods presented: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Basic weighted average number of shares outstanding 152 151 152 151 Dilutive common share equivalents—stock options and other stock awards 2 2 2 2 Diluted weighted average number of shares outstanding 154 153 154 153 During the quarter and six months ended June 29, 2018 , the Company made open market repurchases of its common stock for an aggregate purchase price of $90 million and $100 million , respectively. All shares repurchased were immediately retired.

Supplementary Cash Flow Informa

Supplementary Cash Flow Information and Restricted Cash	6 Months Ended
	Jun. 29, 2018
Supplemental Cash Flow Information [Abstract]
Supplementary Cash Flow Information and Restricted Cash	Note 17–Supplementary Cash Flow Information and Restricted Cash Supplementary cash flow information, and non-cash activities, for the periods presented was as follows: Six Months Ended June 29, June 30, (in millions) Supplementary cash flow information: Cash paid for interest $ 68 $ 59 Cash paid for income taxes, net of refunds 55 107 Non-cash financing activity: Purchase of non-controlling interests 7 — Capital lease obligation — 6 The following is a reconciliation of cash and cash equivalents, as reported within the condensed consolidated balance sheets, to the total cash, cash equivalents and restricted cash, as reported within the condensed consolidated statements of cash flows: June 29, December 29, (in millions) Cash and cash equivalents $ 303 $ 390 Restricted cash 20 32 Total cash, cash equivalents and restricted cash $ 323 $ 422 The restricted cash is recorded within "Inventory, prepaid expenses and other current assets" in the Company's condensed consolidated balance sheets. The restricted cash primarily comprises of advances from customers that are restricted as to use for certain expenditures related to that customer's contract.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 29, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Note 18–Income Taxes In December 2017, the U.S. government enacted the Tax Act which made broad and complex changes to the U.S. tax code, including, but not limited to, (1) reducing the U.S. federal corporate tax rate from 35% to 21%; (2) requiring companies to pay a one-time transition tax on certain unrepatriated earnings of foreign subsidiaries; (3) generally eliminating U.S. federal income taxes on dividends from foreign subsidiaries; and (4) limiting the deductibility of certain executive compensation. As of June 29, 2018 , the Company's accounting for the following elements of the Tax Act is not complete: (1) deemed repatriation tax, (2) cost recovery and (3) limitation on the deductibility of certain executive compensation. However, the Company was able to make reasonable estimates and has recorded provisional amounts. The Company expects to finalize its assessment of all provisional amounts within the allowed one-year measurement period. There are no material elements of the Tax Act for which the Company was unable to make a reasonable estimate. The Company made no changes to fiscal 2017 provisional amounts during the six months ended June 29, 2018 . For the quarter ended June 29, 2018 , the effective tax rate was 12.1% compared to 27.4% for the quarter ended June 30, 2017 . For the six months ended June 29, 2018 , the effective tax rate was 14.8% compared to 29.2% for the six months ended June 30, 2017 . The decrease in the effective tax rate for both periods was primarily due to the Tax Act's reduction of the U.S. federal statutory rate and certain tax benefits related to the anticipated sale of the Company's commercial cybersecurity business, partially offset by a decrease in tax benefits related to employee stock awards.

Business Segments

Business Segments	6 Months Ended
	Jun. 29, 2018
Segment Reporting [Abstract]
Business Segments	Note 19–Business Segments The Company defines its reportable segments based on the way the chief operating decision maker ("CODM"), currently its Chairman and Chief Executive Officer, manages the operations of the Company for purposes of allocating resources and assessing performance. The segment information for the periods presented was as follows: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Revenues: Defense Solutions $ 1,256 $ 1,243 $ 2,434 $ 2,537 Civil 822 875 1,662 1,717 Health 451 454 876 897 Corporate — (1 ) — — Total revenues $ 2,529 $ 2,571 $ 4,972 $ 5,151 Operating income (loss): Defense Solutions $ 93 $ 63 $ 178 $ 142 Civil 61 66 135 120 Health 68 74 110 121 Corporate (23 ) (37 ) (65 ) (76 ) Total operating income $ 199 $ 166 $ 358 $ 307 The financial performance measures used to evaluate segment performance are revenues and operating income. As a result, " Interest expense, net ," " Other income, net " and " Income tax expense ," as reported in the condensed consolidated financial statements are not allocated to the Company's segments. Under U.S. Government Cost Accounting Standards, indirect costs including depreciation expense are collected in numerous indirect cost pools, which are then collectively allocated out to the Company’s reportable segments based on a representative causal or beneficial relationship of the costs in the pool to the costs in the base. As such, the company does not separately disclose depreciation expense on the condensed consolidated statements of income. Asset information by segment is not a key measure of performance used by the CODM.

Contingencies

Contingencies	6 Months Ended
	Jun. 29, 2018
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Note 20–Contingencies Legal Proceedings MSA Joint Venture On November 10, 2015, MSA received a final decision by the Department of Energy ("DoE") contracting officer for the Mission Support Contract concluding that certain payments to MSA by the DoE for the performance of IT services by Lockheed Martin Services, Inc. ("LMSI") under a subcontract to MSA constituted alleged affiliate fees in violation of the FAR. Lockheed Martin Integrated Technology LLC (now known as Leidos Integrated Technology LLC) is a member entity of MSA. Subsequent to the contracting officer's final decision, MSA, LMSI, and Lockheed Martin Corporation received notice from the U.S. Attorney's Office for the Eastern District of Washington that the U.S. government had initiated a False Claims Act investigation into the facts surrounding this dispute, and each of MSA, LMSI and Lockheed Martin Corporation have produced information in response to Civil Investigative Demands from the U.S. Attorney's Office. In addition, the U.S. Attorney's office has advised that a parallel criminal investigation is open, although no subjects or targets of the investigation have been identified. Since this issue first was raised by the DoE, MSA has asserted that the IT services performed by LMSI under a fixed-price/fixed-unit rate subcontract approved by the DoE meet the definition of a "commercial item" under the FAR and any profits earned on that subcontract are permissible. MSA filed an appeal of the contracting officer's decision with the Civilian Board of Contract Appeals and that appeal is pending, but has been stayed pending resolution of the False Claims Act investigation. Subsequent to the filing of MSA's appeal, the contracting officer demanded that MSA reimburse the DoE in the amount of $64 million , which was his estimate of the profits earned during the period from 2010 to 2014 by LMSI. The DoE has deferred collection of $32 million of that demand, pending resolution of the appeal and without prejudice to MSA's position that it is not liable for any of the DOE's $64 million reimbursement claim. MSA and the other member of MSA have indicated that they believe if MSA incurs a liability in this matter, then Leidos Integrated Technology, LLC is responsible to MSA for the loss. Under the terms of the Separation Agreement, Lockheed Martin has agreed to indemnify the Company for 100% of any damages in excess of $38 million up to $64 million , and 50% of any damages in excess of $64 million , with respect to claims asserted against MSA related to this matter. At June 29, 2018 , the Company had a liability of $39 million and an indemnification asset of $1 million recorded in the condensed consolidated balance sheets. Securities Litigation Between February and April 2012, alleged stockholders filed three putative securities class actions against the Company and several former executives relating to the Company's contract to develop and implement an automated time and attendance and workforce management system for certain agencies of the City of New York ("CityTime"). One case was withdrawn and two cases were consolidated in the U.S. District Court for the Southern District of New York in In Re: SAIC, Inc. Securities Litigation . The consolidated securities complaint asserted claims under Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 based on allegations that the Company and individual defendants made misleading statements or omissions about the Company's revenues, operating income and internal controls in connection with disclosures relating to the CityTime project. The plaintiffs sought to recover from the Company and the individual defendants an unspecified amount of damages class members allegedly incurred by buying Leidos' stock at an inflated price. The District Court dismissed the plaintiffs' claims with prejudice and without leave to replead. The plaintiffs then appealed to the United States Court of Appeals for the Second Circuit, which issued an opinion affirming in part, and vacating in part, the District Court's ruling. The Company filed a petition for a writ of certiorari in the U.S. Supreme Court, which was granted on March 27, 2017. The District Court granted the Company's request to stay all proceedings, including discovery, pending the outcome at the Supreme Court. In September 2017, the parties engaged in mediation resulting in an agreement to settle all remaining claims for an immaterial amount to be paid by the Company. The amounts payable by the Company are covered by an insurance policy. The terms of the proposed settlement remain subject to court approval, which is expected to occur in 2018. Greek Government Contract In 2003, the Company entered into an FFP contract with the Hellenic Republic of Greece to provide a Command, Control, Communications, Coordination and Integration System. The Greek government disputed the contract balance owed to the Company and has not paid the Company's final invoice. In 2013, the Company received an arbitral award by the International Chamber of Commerce for €39 million , which has not been satisfied. In January 2017, the U.S. District Court granted an order to enforce the arbitration award and entered judgment in the Company's favor, converting the award to U.S. dollars. The U.S. Court of Appeals for the D.C. Circuit subsequently ruled that the district court judgment should instead reflect the currency in which it was originally awarded. Separately, the Greek government has sought to annul the award through separate litigation in the Greek courts, and such a challenge is currently pending. Based on the complex nature of this contractual situation and the difficulties encountered to date, significant uncertainties exist and the Company is unable to reliably estimate the ultimate outcome. Other The Company is also involved in various claims and lawsuits arising in the normal conduct of its business, none of which, in the opinion of the Company's management, based upon current information, will likely have a material adverse effect on the Company's condensed consolidated financial position, results of operations or cash flows. Other Contingencies VirnetX, Inc. On September 29, 2017, the federal trial court in the Eastern District of Texas entered a final judgment in the VirnetX v. Apple case referred to as the Apple I case. The court found that Apple willfully infringed the VirnetX patents at issue in the Apple I case and awarded enhanced damages, bringing the total award against Apple to over $343 million in pre-interest damages. The court subsequently awarded an additional sum of over $96 million for costs, attorneys' fees, and interest, bringing the total award to VirnetX in the Apple I case to over $439 million . Apple has filed an appeal of the judgment in the Apple I case with the U.S. Court of Appeals for the Federal Circuit. On April 10, 2018, a jury trial concluded in an additional patent infringement case brought by VirnetX against Apple, referred to as the Apple II case, in which the jury returned a verdict against Apple for infringement and awarded VirnetX damages in the amount of over $502 million . On April 11, 2018, in a second phase of the Apple II trial, the jury found Apple's infringement to be willful. Rulings on post-trial motions and/or the court’s final judgment in the Apple II case remain pending. Under its agreements with VirnetX, Leidos would receive 25% of the proceeds obtained by VirnetX after reduction for attorneys' fees and costs. However, the verdicts in these cases remain subject to appeal. In addition, the patents at issue in these cases are subject to U.S. Patent and Trademark Office post-grant inter partes review and/or reexamination proceedings and related appeals, which may result in all or part of these patents being invalidated or the claims of the patents being limited. Thus, no assurances can be given when or if the Company will receive any proceeds in connection with these jury awards. In addition, if the Company receives any proceeds, the Company is required to pay a royalty to the customer who paid for the development of the technology. The Company does not have any assets or liabilities recorded in connection with this matter as of June 29, 2018 . Government Investigations and Reviews The Company is routinely subject to investigations and reviews relating to compliance with various laws and regulations with respect to its role as a contractor to federal, state and local government customers and in connection with performing services in countries outside of the United States. Adverse findings could have a material effect on the Company's business, financial position, results of operations and cash flows due to its reliance on government contracts. Indirect cost audits by the DCAA remain open for fiscal 2014 and subsequent years for Leidos, Inc., and fiscal 2012 and subsequent years for Leidos Innovations. Although the Company has recorded contract revenues based upon an estimate of costs that the Company believes will be approved upon final audit or review, the Company cannot predict the outcome of any ongoing or future audits or reviews and adjustments, and if future adjustments exceed the Company's estimates, its profitability may be adversely affected. As of June 29, 2018 , the Company believes it has adequately reserved for potential adjustments from audits or reviews of contract costs.

Commitments

Commitments	6 Months Ended
	Jun. 29, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments	Note 21–Commitments The Company has outstanding letters of credit of $93 million as of June 29, 2018 , principally related to performance guarantees on contracts. The Company also has outstanding surety bonds with net exposure of $123 million , principally related to performance and subcontractor payment bonds on the Company's contracts. The outstanding letters of credit and surety bonds have various terms with the majority expiring over the next four fiscal years. On January 24, 2018, the Company entered into a lease agreement with its current lessor for office space in a building to be constructed which will function as the Company's new corporate headquarters in Reston, Virginia. The Company will occupy the space for an initial term of 148 months and rent expense will be $11 million for the first lease year, with an annual rent expense increase of 2.5% . The Company currently expects construction to be completed and to take occupancy of the building by April 1, 2020, at which point the Company's lease agreements for its current corporate headquarters will terminate.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 29, 2018
Subsequent Events [Abstract]
Subsequent Events	Note 22–Subsequent Events On July 12, 2018, Leidos and Plainfield entered into an amendment to the Note, allowing Plainfield to defer the maturity of the Note until the earlier of August 24, 2018, or the date Plainfield successfully closes on a refinancing agreement with a third party. See " Note 7–Divestitures " for further details regarding the Company's Note with Plainfield. On July 23, 2018, the Company entered into a Contract of Sale to sell and leaseback one of its properties included within Corporate. The sale is expected to be completed during the fourth quarter of fiscal 2018 at which time the leaseback term will begin. The term of the lease is expected to end during fiscal 2020.

Significant Accounting Polici30

Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 29, 2018
Accounting Policies [Abstract]
Revenue Recognition	Revenue Recognition The Company's revenues from contracts with customers are from offerings including cybersecurity; data analytics; enterprise IT modernization; operations and logistics; sensors, collection and phenomenology; software development; and systems engineering , primarily with the U.S. government and its agencies. The Company also serves various state and local governments, foreign governments and U.S. commercial customers. The Company performs under various types of contracts, which include firm-fixed-price ("FFP"), time-and-materials ("T&M"), fixed-price-level-of-effort ("FP-LOE"), cost-plus-fixed-fee, cost-plus-award-fee, cost-plus-incentive-fee and fixed-price-incentive-fee ("FP-IF") contracts. To determine the proper revenue recognition, the Company first evaluates whether it has a duly approved and enforceable contract with a customer, in which the rights of the parties and payment terms are identified, and collectability is probable. The Company also evaluates whether two or more contracts should be combined and accounted for as a single contract, including the task orders issued under an indefinite delivery/indefinite quantity ("IDIQ") award. In addition, the Company assesses contract modifications to determine whether changes to existing contracts should be accounted for as part of the original contract or as a separate contract. Contract modifications for the Company generally relate to changes in contract specifications and requirements and do not add distinct services, and therefore are accounted for as part of the original contract. If contract modifications add distinct goods or services and increase the contract value by an amount that reflects the standalone selling price, those modifications are accounted for as separate contracts. Most of the Company's contracts comprise multiple promises including the design and build of software-based systems, integration of hardware and software solutions, running and maintaining of IT infrastructure and procurement services. In all cases, the Company assesses if the multiple promises should be accounted for as separate performance obligations or combined into a single performance obligation. The Company generally separates multiple promises in a contract as separate performance obligations if those promises are distinct, both individually and in the context of the contract. If multiple promises in a contract are highly interrelated or comprise a series of distinct services performed over time, they are combined and accounted for as a single performance obligation. The Company's contracts with the U.S. government often contain options to renew existing contracts for an additional period of time (generally a year at a time) under the same terms and conditions as the original contract, and generally do not provide the customer any material rights under the contract. The Company accounts for renewal options as separate contracts when they include distinct goods or services at standalone selling prices. Contracts with the U.S. government are subject to the Federal Acquisition Regulation ("FAR") and priced on estimated or actual costs of providing the goods or services. The FAR provides guidance on types of costs that are allowable in establishing prices for goods and services provided to the U.S. government and its agencies. Each contract is competitively priced and bid separately. Pricing for non-U.S. government agencies and commercial customers is based on specific negotiations with each customer. The Company excludes any taxes collected or imposed when determining the transaction price. Certain of the Company's cost-plus and fixed-price contracts contain award fees, incentive fees or other provisions that may either increase or decrease the transaction price. These variable amounts generally are awarded upon achievement of certain performance metrics, program milestones or cost targets and can be based upon customer discretion. The Company estimates variable consideration at the most probable amount that it expects to be entitled to, based on the assessment of the contractual variable fee criteria, complexity of work and related risks, extent of customer discretion, amount of variable consideration received historically and the potential of significant reversal of revenue. The Company allocates the transaction price of a contract to its performance obligations in the proportion of its respective standalone selling prices. The standalone selling price of the Company's performance obligations is generally based on an expected cost-plus margin approach, in accordance with the FAR. For certain product sales, the Company uses prices from other standalone sales. Substantially all of the Company's contracts do not contain a significant financing component, which would require an adjustment to the transaction price of the contract. The Company recognizes revenue on its service based contracts primarily over time as there is continuous transfer of control to the customer over the duration of the contract as the Company performs the promised services. For U.S. government contracts, continuous transfer of control to the customer is evidenced by clauses in the contract that allow the customer to unilaterally terminate the contract for convenience, pay for costs incurred plus a reasonable profit and take control of any work-in-process. Similarly, for non-U.S. government contracts, the customer typically controls the work-in-process as evidenced by rights to payment for work performed to date plus a reasonable profit to deliver products or services that do not have an alternate use to the Company. Anticipated losses on service based contracts are recognized as incurred. In certain product sales, where the products have an alternate use, the Company recognizes revenue at a point in time when the customer takes control of the asset usually denoted by possession and legal title. On FFP contracts, revenue recognized over time generally uses a method that measures the extent of progress towards completion of a performance obligation, principally using a cost-input method (referred to as the cost-to-cost method). Under the cost-to-cost method, revenue is recognized based on the proportion of total cost incurred to estimated total costs-at-completion ("EAC"). A performance obligation's EAC includes all direct costs such as materials, labor, subcontract costs, overhead, and a ratable portion of general and administrative costs. In addition, the Company includes in an EAC of a performance obligation future losses estimated to be incurred on onerous contracts, as and when known, and the most likely amount of transaction price (revenue) that the Company expects to receive for unpriced change orders (modifications). On certain other contracts, principally T&M, FP-LOE, and cost-plus, revenue is recognized using the right-to-invoice practical expedient as the Company is contractually able to invoice the customer based on the control transferred to the customer. Additionally, on maintenance (generally FFP) performance obligations, revenue is recognized over time using a straight-line method as the control of the services is provided to the customer evenly over the period of performance. For certain performance obligations, the Company is not primarily responsible for fulfilling the promise to provide the goods or service to the customer, does not have inventory risk and does not have discretion in establishing the price for the goods or service. In such cases, the Company recognizes revenue on a net basis. Contract costs generally include direct costs such as materials, labor, subcontract costs, and indirect costs identifiable with or allocable to a specific contract. Costs are expensed as incurred except for costs incurred during the transition phase of a new contract, which are capitalized and amortized on a straight-line basis over the expected life of that contract. The Company does not incur significant incremental costs to acquire contracts. Contract costs incurred for U.S. government contracts, including indirect costs, are subject to audit and adjustment by the Defense Contract Audit Agency ("DCAA") (see " Note 20–Contingencies ").
Changes In Estimates On Contracts	The impact on diluted EPS attributable to Leidos common stockholders is calculated using the Company's statutory tax rate. Changes in Estimates on Contracts Changes in estimates related to contracts accounted for using the cost-to-cost method of accounting are recognized in the period in which such changes are made for the inception-to-date effect of the changes, with the exception of contracts acquired through the acquisition of Lockheed Martin's Information Systems & Global Solutions business ("IS&GS Business") (see " Note 6–Acquisitions "), where the adjustment is made for the period commencing from the date of acquisition.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company's cash equivalents are primarily comprised of investments in several large institutional money market funds and bank deposits, with original maturity of three months or less. The Company includes outstanding payments within "Cash and cash equivalents" and correspondingly increases "Accounts payable and accrued liabilities" on the condensed consolidated balance sheets.
Receivables	Receivables The Company's receivables include amounts billed and currently due from customers, amounts billable where the right to consideration is unconditional and amounts unbilled. Amounts billable and unbilled amounts are recognized at estimated realizable value and consist of costs and fees, substantially all of which are expected to be billed and collected generally within one year. Unbilled amounts also include rate variances that are billable upon negotiation of final indirect rates with the DCAA. The typical billing for the Company's cost-reimbursable and T&M contracts is as costs are incurred. FFP contracts are billed either based on milestones, which are the achievement of specific events as defined in the contract, or based on progress payments, which are interim payments up to a designated amount of costs incurred as work progresses. On certain contracts, the customer withholds a certain percentage of the contract price (retainage). These withheld amounts are included within the Company's unbilled receivables and are billed upon contract completion or the occurrence of a specified event, and when negotiation of final indirect rates with the U.S. government is complete. Based on the Company's historical experience, the write-offs of retention balances have not been significant. When events or conditions indicate that amounts outstanding from customers may become uncollectible, an allowance is estimated and recorded. Amounts billed and collected on contracts but not yet recorded as revenue because the Company has not performed its obligation under the arrangement with a customer are deferred and included within "Accounts payable and accrued liabilities" or "Other long-term liabilities" on the condensed consolidated balance sheets.

Accounting Standards (Tables)

Accounting Standards (Tables)	6 Months Ended
	Jun. 29, 2018
Accounting Changes and Error Corrections [Abstract]
Schedule of cumulative effect of the changes made to the Company’s consolidated balance sheet for the adoption of the ASUs	The cumulative effect of the changes made to the Company's condensed consolidated balance sheet for the adoptions of the ASUs above was as follows: Balance at December 29, 2017 Adjustments due to ASU 2014-09 Adjustments due to ASU 2017-12 Adjustments due to ASU 2018-02 Balance at December 30, 2017 (in millions) Assets: Receivables, net $ 1,831 $ 4 $ — $ — $ 1,835 Inventory, prepaid expenses and other current assets 453 (3 ) — — 450 Equity: Accumulated deficit $ (7 ) $ 1 $ (3 ) $ (6 ) $ (15 ) Accumulated other comprehensive income 33 — 3 6 42 The effects to the condensed consolidated financial statements at June 29, 2018 , as a result of applying ASC 606, rather than previous GAAP ("ASC 605"), were the following: Balance Sheet As Reported (ASC 606) As Adjusted (ASC 605) (in millions) Receivables, net $ 1,779 $ 1,775 Inventory, prepaid expenses and other current assets 458 461 Accumulated earnings (deficit) 133 132 Income Statement Three Months Ended June 29, 2018 Six Months Ended June 29, 2018 As Reported (ASC 606) As Adjusted As Reported (ASC 606) As Adjusted (in millions) Revenues $ 2,529 $ 2,530 $ 4,972 $ 4,968 Cost of revenues 2,152 2,152 4,238 4,235 Operating income 199 200 358 357

Significant Accounting Polici32

Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 29, 2018
Accounting Policies [Abstract]
Schedule of changes In estimates on contracts	Changes in estimates on contracts for the periods presented were as follows: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions, except per share amounts) Net favorable impact to income before income taxes $ 34 $ 40 $ 69 $ 62 Impact on diluted EPS attributable to Leidos common stockholders $ 0.17 $ 0.17 $ 0.34 $ 0.26

Revenues (Tables)

Revenues (Tables)	6 Months Ended
	Jun. 29, 2018
Revenue from Contract with Customer [Abstract]
Schedule of cumulative effect of the changes made to the Company’s consolidated balance sheet for the adoption of the ASUs	The cumulative effect of the changes made to the Company's condensed consolidated balance sheet for the adoptions of the ASUs above was as follows: Balance at December 29, 2017 Adjustments due to ASU 2014-09 Adjustments due to ASU 2017-12 Adjustments due to ASU 2018-02 Balance at December 30, 2017 (in millions) Assets: Receivables, net $ 1,831 $ 4 $ — $ — $ 1,835 Inventory, prepaid expenses and other current assets 453 (3 ) — — 450 Equity: Accumulated deficit $ (7 ) $ 1 $ (3 ) $ (6 ) $ (15 ) Accumulated other comprehensive income 33 — 3 6 42 The effects to the condensed consolidated financial statements at June 29, 2018 , as a result of applying ASC 606, rather than previous GAAP ("ASC 605"), were the following: Balance Sheet As Reported (ASC 606) As Adjusted (ASC 605) (in millions) Receivables, net $ 1,779 $ 1,775 Inventory, prepaid expenses and other current assets 458 461 Accumulated earnings (deficit) 133 132 Income Statement Three Months Ended June 29, 2018 Six Months Ended June 29, 2018 As Reported (ASC 606) As Adjusted As Reported (ASC 606) As Adjusted (in millions) Revenues $ 2,529 $ 2,530 $ 4,972 $ 4,968 Cost of revenues 2,152 2,152 4,238 4,235 Operating income 199 200 358 357
Schedule of disaggregated revenue	Disaggregated revenues by geographic location were as follows: Three Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) United States $ 1,164 $ 693 $ 451 $ 2,308 International 92 129 — 221 Total $ 1,256 $ 822 $ 451 $ 2,529 Six Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) United States $ 2,252 $ 1,389 $ 876 $ 4,517 International 182 273 — 455 Total $ 2,434 $ 1,662 $ 876 $ 4,972 Disaggregated revenues by contract-type were as follows: Three Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) Cost-reimbursement and fixed price-incentive fee $ 860 $ 475 $ 42 $ 1,377 Firm-fixed-price 259 203 284 746 Time and materials and fixed-price-level-of-effort 137 144 125 406 Total $ 1,256 $ 822 $ 451 $ 2,529 Six Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) Cost-reimbursement and fixed price-incentive fee $ 1,631 $ 914 $ 92 $ 2,637 Firm-fixed-price 542 459 537 1,538 Time and materials and fixed-price-level-of-effort 261 289 247 797 Total $ 2,434 $ 1,662 $ 876 $ 4,972 Disaggregated revenues by customer-type were as follows: Three Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) DoD $ 1,099 $ 26 $ 82 $ 1,207 Other government agencies (1) 50 574 327 951 Commercial and non-U.S. customers 107 222 42 371 Total $ 1,256 $ 822 $ 451 $ 2,529 Six Months Ended June 29, 2018 Defense Solutions Civil Health Total (in millions) DoD $ 2,131 $ 49 $ 174 $ 2,354 Other government agencies (1) 95 1,163 625 1,883 Commercial and non-U.S. customers 208 450 77 735 Total $ 2,434 $ 1,662 $ 876 $ 4,972

Contract Asset and Liabilities

Contract Asset and Liabilities (Tables)	6 Months Ended
	Jun. 29, 2018
Revenue from Contract with Customer [Abstract]
Components of contract assets and contract liabilities	The components of contract assets and contract liabilities consisted of the following: Balance sheet line item June 29, December 30, 2017 (1) (in millions) Contract assets - current: Unbilled receivables (2) Receivables, net $ 734 $ 844 Transition costs and project assets Inventory, prepaid expenses and other current assets 83 59 $ 817 $ 903 Contract assets - non-current: Transition costs and project assets Other assets $ 11 $ 13 Contract liabilities - current: Deferred revenue Accounts payable and accrued liabilities $ 311 $ 293 Contract liabilities - non-current: Deferred revenue Other long-term liabilities $ 12 $ 17 (1) Includes the cumulative effect of the changes made to the Company's opening balance sheet at December 30, 2017, as a result of the adoption of ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . (2) Balances exclude $434 million and $234 million determined to be billable at June 29, 2018 , and December 30, 2017, respectively.

Acquisitions (Tables)

Acquisitions (Tables)	6 Months Ended
	Jun. 29, 2018
Business Combinations [Abstract]
Schedule of expenses related to the acquisition and integration of the IS&GS Business	The Company incurred the following expenses related to the acquisition and integration of the IS&GS Business: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Acquisition costs $ — $ — $ — $ 1 Integration costs (1) 7 16 22 34 Total acquisition and integration costs $ 7 $ 16 $ 22 $ 35 (1) For the quarter and six months ended June 29, 2018 , the Company reclassified $4 million from restructuring expenses to integration costs.

Divestiture (Tables)

Divestiture (Tables)	6 Months Ended
	Jun. 29, 2018
Discontinued Operations and Disposal Groups [Abstract]
The major classes of assets and liabilities classified as held for sale	The major classes of assets and liabilities classified as held for sale were as follows: June 29, (in millions) Receivables, net $ 21 Inventory, prepaid expenses and other current assets 3 Property, plant and equipment, net 3 Intangible assets, net 5 Goodwill 57 Deferred tax assets 10 Total assets held for sale $ 99 Accounts payable and accrued liabilities $ 12 Accrued payroll and employee benefits 5 Other long-term liabilities 5 Total liabilities held for sale $ 22

Restructuring Expenses (Tables)

Restructuring Expenses (Tables)	6 Months Ended
	Jun. 29, 2018
Restructuring and Related Activities [Abstract]
Schedule of restructuring expenses	The restructuring expenses related to this program were as follows: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Severance costs $ — $ 2 $ 1 $ 12 Lease termination expenses (1) 1 4 2 7 Restructuring expenses related to the IS&GS Business $ 1 $ 6 $ 3 $ 19 (1) For the quarter and six months ended June 29, 2018 , the Company reclassified $4 million from restructuring expenses to integration costs.
Schedule of restructuring liability	The restructuring liability related to this program was as follows: Severance Costs Lease Termination Expenses Total (in millions) Balance as of December 30, 2016 $ 7 $ 1 $ 8 Charges 18 19 37 Cash payments (20 ) (16 ) (36 ) Balance as of December 29, 2017 5 4 9 Charges (1) 1 2 3 Cash payments (2) (6 ) (2 ) (8 ) Balance as of June 29, 2018 $ — $ 4 $ 4 (1) Includes a reclassification of $4 million from restructuring to integration. (2) Includes a reclassification for payments of $3 million from restructuring to integration.

Goodwill (Tables)

Goodwill (Tables)	6 Months Ended
	Jun. 29, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of carrying amount of goodwill by reportable segment	The following table presents changes in the carrying amount of goodwill by reportable segment: Defense Solutions Civil Health Total (in millions) Goodwill at December 30, 2016 $ 1,954 $ 1,731 $ 937 $ 4,622 Adjustment to original purchase price allocation 94 259 (16 ) 337 Foreign currency translation adjustments 7 8 — 15 Goodwill at December 29, 2017 2,055 1,998 921 4,974 Foreign currency translation adjustments (25 ) (5 ) — (30 ) Transfers to assets held for sale — (57 ) — (57 ) Goodwill at June 29, 2018 $ 2,030 $ 1,936 $ 921 $ 4,887

Intangible Assets (Tables)

Intangible Assets (Tables)	6 Months Ended
	Jun. 29, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of intangible assets	Intangible assets consisted of the following: June 29, 2018 December 29, 2017 Gross carrying value Accumulated amortization Net carrying value Gross carrying value Accumulated amortization Net carrying value (in millions) Finite-lived intangible assets: Program and contract intangibles $ 1,005 $ (281 ) $ 724 $ 1,013 $ (187 ) $ 826 Software and technology 89 (68 ) 21 89 (64 ) 25 Customer relationships 4 (4 ) — 4 (3 ) 1 Backlog — — — 158 (158 ) — Total finite-lived intangible assets 1,098 (353 ) 745 1,264 (412 ) 852 Indefinite-lived intangible assets: Trade names 4 — 4 4 — 4 Total intangible assets $ 1,102 $ (353 ) $ 749 $ 1,268 $ (412 ) $ 856
Schedule of estimated annual amortization expense	The estimated annual amortization expense as of June 29, 2018 , was as follows: Fiscal Year Ending (in millions) 2018 (remainder of year) $ 100 2019 170 2020 126 2021 105 2022 92 2023 and thereafter 152 $ 745

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	6 Months Ended
	Jun. 29, 2018
Property, Plant and Equipment [Abstract]
Schedule of Property, plant and equipment, net	Property, plant and equipment, net consisted of the following: June 29, December 29, (in millions) Computers and other equipment $ 188 $ 194 Leasehold improvements 186 171 Buildings and improvements 56 54 Office furniture and fixtures 35 34 Construction in progress 45 44 Land 40 49 550 546 Less: accumulated depreciation (329 ) (314 ) $ 221 $ 232

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 29, 2018
Fair Value Disclosures [Abstract]
Schedule of financial assets measured on a recurring basis	The Company's financial instruments measured at fair value on a recurring basis consisted of the following: June 29, 2018 December 29, 2017 Carrying value Fair value Carrying value Fair value (in millions) Financial assets: Derivatives $ 55 $ 55 $ 37 $ 37 Financial liabilities: Derivatives 7 7 — —

Derivative Instruments (Tables)

Derivative Instruments (Tables)	6 Months Ended
	Jun. 29, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of fair value of the Company's interest rate swaps	The fair value of the Company's interest rate swaps was as follows: Asset Derivatives Balance sheet line item June 29, December 29, (in millions) Cash flow interest rate swaps Other assets $ 55 $ 37 Liability Derivatives Balance sheet line item June 29, December 29, (in millions) Fair value interest rate swaps Other long-term liabilities $ 7 $ —
The following amounts were recorded on the consolidated balance sheets related to cumulative basis adjustments for fair value hedges	The following amounts were recorded on the condensed consolidated balance sheets related to cumulative basis adjustments for fair value hedges: Carrying amount of hedged item Cumulative amount of fair value adjustment included within the hedged item Balance sheet line item of hedged item June 29, December 29, June 29, December 29, (in millions) Long-term debt, net of current portion $ 442 $ 449 $ (7 ) $ —
Schedule of effect of the Company's cash flow hedges on other comprehensive income and earnings	The effect of the Company's cash flow hedges on other comprehensive income and earnings for the periods presented was as follows: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Total interest expense, net presented in the condensed consolidated statements of income in which the effects of cash flow hedges are recorded $ 35 $ 34 $ 69 $ 70 Amount recognized in other comprehensive income 7 (4 ) 21 (3 ) Amount reclassified from accumulated other comprehensive income to interest expense, net (2 ) — (3 ) 1

Debt (Tables)

Debt (Tables)	6 Months Ended
	Jun. 29, 2018
Debt Disclosure [Abstract]
Schedule of notes payable and long-term debt	The Company's debt consisted of the following: Stated interest rate Effective interest rate June 29, 2018 (1) December 29, 2017 (1) (in millions) Senior secured notes: $450 million notes, due December 2020 4.45% 4.53% $ 442 $ 449 $300 million notes, due December 2040 5.95% 6.03% 216 216 Senior secured term loans: $690 million Term Loan A, due August 2022 3.88% 4.38% 625 644 $310 million Term Loan A, due August 2022 3.88% 4.37% 262 270 $1,131 million Term Loan B, due August 2023 3.88% 4.26% 1,091 1,101 Senior unsecured notes: $250 million notes, due July 2032 7.13% 7.43% 246 246 $300 million notes, due July 2033 5.50% 5.88% 158 158 Capital leases and notes payable due on various dates through fiscal 2022 0%-5.55% Various 21 27 Total long-term debt 3,061 3,111 Less: current portion 71 55 Total long-term debt, net of current portion $ 2,990 $ 3,056

Accumulated Other Comprehensi44

Accumulated Other Comprehensive Income (Tables)	6 Months Ended
	Jun. 29, 2018
Equity [Abstract]
Schedule of Changes in the components of accumulated other comprehensive income	Changes in the components of accumulated other comprehensive income were as follows: Foreign currency translation adjustments Unrecognized gain on derivative instruments Pension adjustments Total accumulated other comprehensive income (in millions) Balance at December 30, 2016 $ (7 ) $ 10 $ (7 ) $ (4 ) Other comprehensive income 36 10 9 55 Taxes (12 ) (6 ) — (18 ) Balance at December 29, 2017 17 14 2 33 Cumulative adjustments related to ASU adoptions (Note 2) 3 10 (4 ) 9 Balance at December 30, 2017 20 24 (2 ) 42 Other comprehensive (loss) income (38 ) 21 — (17 ) Taxes 5 (4 ) — 1 Reclassification from accumulated other comprehensive income — (3 ) — (3 ) Balance at June 29, 2018 $ (13 ) $ 38 $ (2 ) $ 23

Earnings Per Share (EPS) (Table

Earnings Per Share (EPS) (Tables)	6 Months Ended
	Jun. 29, 2018
Earnings Per Share [Abstract]
Reconciliation of the weighted average number of shares outstanding used to compute basic and diluted EPS	The following table provides a reconciliation of the weighted average number of shares outstanding used to compute basic and diluted EPS for the periods presented: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Basic weighted average number of shares outstanding 152 151 152 151 Dilutive common share equivalents—stock options and other stock awards 2 2 2 2 Diluted weighted average number of shares outstanding 154 153 154 153

Supplementary Cash Flow Infor46

Supplementary Cash Flow Information and Restricted Cash (Tables)	6 Months Ended
	Jun. 29, 2018
Supplemental Cash Flow Information [Abstract]
Schedule of supplementary cash flow information	Supplementary cash flow information, and non-cash activities, for the periods presented was as follows: Six Months Ended June 29, June 30, (in millions) Supplementary cash flow information: Cash paid for interest $ 68 $ 59 Cash paid for income taxes, net of refunds 55 107 Non-cash financing activity: Purchase of non-controlling interests 7 — Capital lease obligation — 6 The following is a reconciliation of cash and cash equivalents, as reported within the condensed consolidated balance sheets, to the total cash, cash equivalents and restricted cash, as reported within the condensed consolidated statements of cash flows: June 29, December 29, (in millions) Cash and cash equivalents $ 303 $ 390 Restricted cash 20 32 Total cash, cash equivalents and restricted cash $ 323 $ 422

Business Segments (Tables)

Business Segments (Tables)	6 Months Ended
	Jun. 29, 2018
Segment Reporting [Abstract]
Schedule of segment reporting information by segment	The segment information for the periods presented was as follows: Three Months Ended Six Months Ended June 29, June 30, June 29, June 30, (in millions) Revenues: Defense Solutions $ 1,256 $ 1,243 $ 2,434 $ 2,537 Civil 822 875 1,662 1,717 Health 451 454 876 897 Corporate — (1 ) — — Total revenues $ 2,529 $ 2,571 $ 4,972 $ 5,151 Operating income (loss): Defense Solutions $ 93 $ 63 $ 178 $ 142 Civil 61 66 135 120 Health 68 74 110 121 Corporate (23 ) (37 ) (65 ) (76 ) Total operating income $ 199 $ 166 $ 358 $ 307

Nature of Operations and Basi48

Nature of Operations and Basis of Presentation (Additional Information) (Detail) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2017USD ($)	Jun. 29, 2018USD ($)segment	Jun. 30, 2017USD ($)	Jan. 26, 2018	Jan. 25, 2018
Significant Accounting Policies [Line Items]
Number of reportable segments | segment		3
Increase in cash, cash equivalents and restricted cash		$ (99)	$ (109)
Increase in cash due to operating activities		293	95
Decrease in cash due to financing activities		$ 5	1
Cost of Revenue
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	$ (43)		(80)
Selling, General and Administrative Expenses
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	$ 43		80
Accounting Standards Update 2016-18
Significant Accounting Policies [Line Items]
Net increase in operating cash flows			5
Increase in cash, cash equivalents and restricted cash			5
Accounting Standards Update 2016-15
Significant Accounting Policies [Line Items]
Increase in cash due to operating activities			(1)
Decrease in cash due to financing activities			$ 1
Jacob's Group's Interest in MSA | Mission Support Alliance
Significant Accounting Policies [Line Items]
Voting interest acquired				100.00%
Mission Support Alliance, LLC
Significant Accounting Policies [Line Items]
Controlling ownership interest				88.00%	47.00%
Mission Support Alliance, LLC | Mission Support Alliance
Significant Accounting Policies [Line Items]
Voting interest acquired				41.00%

Accounting Standards (Details)

Accounting Standards (Details) - USD ($) $ in Millions	Jun. 29, 2018	Dec. 30, 2017	Dec. 29, 2017
ASSETS
Receivables, net	$ 1,779	$ 1,835	$ 1,831
Inventory, prepaid expenses and other current assets	458	450	453
Equity
Accumulated earnings (deficit)	133	(15)	(7)
Accumulated other comprehensive income	$ 23	42	$ 33
Adjustments due to ASU 2014-09
ASSETS
Receivables, net		4
Inventory, prepaid expenses and other current assets		(3)
Equity
Accumulated earnings (deficit)		1
Accumulated other comprehensive income		0
Adjustments due to ASU 2017-12
ASSETS
Receivables, net		0
Inventory, prepaid expenses and other current assets		0
Equity
Accumulated earnings (deficit)		(3)
Accumulated other comprehensive income		3
Adjustments due to ASU 2018-02
ASSETS
Receivables, net		0
Inventory, prepaid expenses and other current assets		0
Equity
Accumulated earnings (deficit)		(6)
Accumulated other comprehensive income		$ 6

Significant Accounting Polici50

Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Dec. 29, 2017
Significant Accounting Policies [Line Items]
Net favorable impact to income before income taxes	$ 34	$ 40	$ 69	$ 62
Impact on diluted EPS attributable to Leidos common stockholders (usd per share)	$ 0.17	$ 0.17	$ 0.34	$ 0.26
Revenue recognized for performance obligation satisfied in the previous periods	$ 32		$ 66
Accounts payable and accrued liabilities	1,461		1,461		$ 1,639
Cash and Cash Equivalents
Significant Accounting Policies [Line Items]
Accounts payable and accrued liabilities	$ 63		$ 63		$ 169

Revenues (Dual Reporting) (Deta

Revenues (Dual Reporting) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Dec. 30, 2017	Dec. 29, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Receivables, net	$ 1,779		$ 1,779		$ 1,835	$ 1,831
Inventory, prepaid expenses and other current assets	458		458		450	453
Accumulated earnings (deficit)	133		133		$ (15)	$ (7)
Revenues	2,529	$ 2,571	4,972	$ 5,151
Cost of revenues	2,152	2,190	4,238	4,423
Operating income	199	$ 166	358	$ 307
As Adjusted
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Receivables, net	1,775		1,775
Inventory, prepaid expenses and other current assets	461		461
Accumulated earnings (deficit)	132		132
Revenues	2,530		4,968
Cost of revenues	2,152		4,235
Operating income	$ 200		$ 357

Revenues (Narrative) (Details)

Revenues (Narrative) (Details) $ in Billions	Jun. 29, 2018USD ($)
Revenue from Contract with Customer [Abstract]
Remaining performance obligations, which are expected to be recognized as revenue	$ 9
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-06-30
Revenue from Contract with Customer [Abstract]
Remaining performance obligations, which are expected to be recognized as revenue	$ 4.6
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligations, which are expected to be recognized as revenue, ( in months/years)	6 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-12-29
Revenue from Contract with Customer [Abstract]
Remaining performance obligations, which are expected to be recognized as revenue	$ 2
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligations, which are expected to be recognized as revenue, ( in months/years)	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-12-28
Revenue from Contract with Customer [Abstract]
Remaining performance obligations, which are expected to be recognized as revenue	$ 2.4
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligations, which are expected to be recognized as revenue, ( in months/years)

Revenues (Disaggregation of rev

Revenues (Disaggregation of revenue) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Disaggregation of Revenue [Line Items]
Revenues	$ 2,529	$ 2,571	$ 4,972	$ 5,151
United States
Disaggregation of Revenue [Line Items]
Revenues	2,308		4,517
International
Disaggregation of Revenue [Line Items]
Revenues	221		455
Cost-reimbursement and fixed price-incentive fee
Disaggregation of Revenue [Line Items]
Revenues	1,377		2,637
Firm-fixed-price
Disaggregation of Revenue [Line Items]
Revenues	746		1,538
Time and materials and fixed-price-level-of-effort
Disaggregation of Revenue [Line Items]
Revenues	406		797
DoD
Disaggregation of Revenue [Line Items]
Revenues	1,207		2,354
Other government agencies
Disaggregation of Revenue [Line Items]
Revenues	951		1,883
Commercial and non-U.S. customers
Disaggregation of Revenue [Line Items]
Revenues	371		735
Defense Solutions
Disaggregation of Revenue [Line Items]
Revenues	1,256		2,434
Defense Solutions | United States
Disaggregation of Revenue [Line Items]
Revenues	1,164		2,252
Defense Solutions | International
Disaggregation of Revenue [Line Items]
Revenues	92		182
Defense Solutions | Cost-reimbursement and fixed price-incentive fee
Disaggregation of Revenue [Line Items]
Revenues	860		1,631
Defense Solutions | Firm-fixed-price
Disaggregation of Revenue [Line Items]
Revenues	259		542
Defense Solutions | Time and materials and fixed-price-level-of-effort
Disaggregation of Revenue [Line Items]
Revenues	137		261
Defense Solutions | DoD
Disaggregation of Revenue [Line Items]
Revenues	1,099		2,131
Defense Solutions | Other government agencies
Disaggregation of Revenue [Line Items]
Revenues	50		95
Defense Solutions | Commercial and non-U.S. customers
Disaggregation of Revenue [Line Items]
Revenues	107		208
Civil
Disaggregation of Revenue [Line Items]
Revenues	822		1,662
Civil | United States
Disaggregation of Revenue [Line Items]
Revenues	693		1,389
Civil | International
Disaggregation of Revenue [Line Items]
Revenues	129		273
Civil | Cost-reimbursement and fixed price-incentive fee
Disaggregation of Revenue [Line Items]
Revenues	475		914
Civil | Firm-fixed-price
Disaggregation of Revenue [Line Items]
Revenues	203		459
Civil | Time and materials and fixed-price-level-of-effort
Disaggregation of Revenue [Line Items]
Revenues	144		289
Civil | DoD
Disaggregation of Revenue [Line Items]
Revenues	26		49
Civil | Other government agencies
Disaggregation of Revenue [Line Items]
Revenues	574		1,163
Civil | Commercial and non-U.S. customers
Disaggregation of Revenue [Line Items]
Revenues	222		450
Health
Disaggregation of Revenue [Line Items]
Revenues	451		876
Health | United States
Disaggregation of Revenue [Line Items]
Revenues	451		876
Health | International
Disaggregation of Revenue [Line Items]
Revenues	0		0
Health | Cost-reimbursement and fixed price-incentive fee
Disaggregation of Revenue [Line Items]
Revenues	42		92
Health | Firm-fixed-price
Disaggregation of Revenue [Line Items]
Revenues	284		537
Health | Time and materials and fixed-price-level-of-effort
Disaggregation of Revenue [Line Items]
Revenues	125		247
Health | DoD
Disaggregation of Revenue [Line Items]
Revenues	82		174
Health | Other government agencies
Disaggregation of Revenue [Line Items]
Revenues	327		625
Health | Commercial and non-U.S. customers
Disaggregation of Revenue [Line Items]
Revenues	$ 42		$ 77

Contract Asset and Liabilitie54

Contract Asset and Liabilities (Details) - USD ($) $ in Millions	Jun. 29, 2018	Dec. 30, 2017	Jun. 29, 2018	Jun. 29, 2018	Dec. 29, 2017
Schedule Of Contract Assets And Liabilities [Line Items]
Contract assets - current	$ 817		$ 817	$ 817	$ 903
Contract assets - non-current	11		11	11	13
Contract liabilities - current	311		311	311	293
Contract liabilities - non-current	12		12	12	17
Contract assets part of receivable	434	$ 234
Contract liability revenue recognized			72	127
Amortization of transition and project cots			37	40
Receivables, net
Schedule Of Contract Assets And Liabilities [Line Items]
Contract assets - current	734		734	734	844
Inventory, prepaid expenses and other current assets
Schedule Of Contract Assets And Liabilities [Line Items]
Contract assets - current	$ 83		$ 83	$ 83	$ 59

Acquisitions (Textual) (Details

Acquisitions (Textual) (Details) - USD ($) $ in Millions	Jan. 18, 2018	Jun. 29, 2018	Jun. 29, 2018	Jun. 30, 2017
Business Acquisition [Line Items]
Cash paid, operating activities			$ (293)	$ (95)
Cash paid, investing activities			109	14
Payment of Tax Indemnification Liability		$ (23)	23	$ 0
Integration costs		$ 4	$ 4
Information Systems & Global Solutions Business of Lockheed Martin
Business Acquisition [Line Items]
Business combination, working capital amount paid	$ 105
Cash paid, operating activities	24
Cash paid, investing activities	$ 81

Acquisitions (Integration Costs

Acquisitions (Integration Costs) (Details) - Information Systems & Global Solutions Business of Lockheed Martin - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Business Acquisition [Line Items]
Acquisition costs	$ 0	$ 0	$ 0	$ 1
Integration costs	7	16	22	34
Total acquisition and integration costs	$ 7	$ 16	$ 22	$ 35

Divestitures (Balance sheet) (D

Divestitures (Balance sheet) (Details) - USD ($) $ in Millions	Jun. 29, 2018	Dec. 29, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale	$ 99	$ 0
Total liabilities held for sale	22	$ 0
Civil | Cybersecurity Business | Disposal Group, Held-for-sale or Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Receivables, net	21
Inventory, prepaid expenses and other current assets	3
Property, plant and equipment, net	3
Intangible assets, net	5
Goodwill	57
Deferred tax assets	10
Assets held for sale	99
Accounts payable and accrued liabilities	12
Accrued payroll and employee benefits	5
Other long-term liabilities	5
Total liabilities held for sale	$ 22

Divestitures (Narrative) (Detai

Divestitures (Narrative) (Details) - Disposal Group, Disposed of by Sale, Not Discontinued Operations - Plainfield $ in Millions	Jul. 24, 2015USD ($)	Dec. 29, 2017USD ($)	Jun. 30, 2017USD ($)extension	Mar. 31, 2017USD ($)	Jun. 29, 2018USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal, consideration	$ 102
Proceeds from divestiture of interest	29
Amount of consideration received	$ 73
Proceeds from collections on promissory note				$ 6
Option to extend for one year period, number | extension			3
Period of extension			1 year
Note receivable, interest rate, stated	6.00%
Note receivable, interest rate, stated, after maturity was extended beyond July 24, 2017			8.00%
Collection deferred			$ 4
Expected settlement amount		$ 40			$ 40
Impairment charge for the note		$ 33
Expected settlement, percentage					50.00%

Restructuring Expenses (Details

Restructuring Expenses (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended	24 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Dec. 29, 2017	Jun. 29, 2018
Restructuring Reserve [Roll Forward]
Restructuring expenses						$ 52
Integration costs	$ 4		$ 4
Payment for integration costs			3
Restructuring Due To IS&GS Acquisition
Restructuring Reserve [Roll Forward]
Restructuring reserve, opening balance			9	$ 8	$ 8
Restructuring expenses	1	$ 6	3	19	37
Cash payments			(8)		(36)
Restructuring reserve, closing balance	4		4		9	4
Restructuring Due To IS&GS Acquisition | Severance costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, opening balance			5	7	7
Restructuring expenses	0	2	1	12	18
Cash payments			(6)		(20)
Restructuring reserve, closing balance	0		0		5	0
Restructuring Due To IS&GS Acquisition | Lease Termination Expenses
Restructuring Reserve [Roll Forward]
Restructuring reserve, opening balance			4	1	1
Restructuring expenses	1	$ 4	2	$ 7	19
Cash payments			(2)		(16)
Restructuring reserve, closing balance	$ 4		$ 4		$ 4	$ 4

Goodwill (Schedule of Changes i

Goodwill (Schedule of Changes in Goodwill by Segment) (Detail) - USD ($)	6 Months Ended		12 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Dec. 29, 2017	Dec. 30, 2016
Goodwill [Roll Forward]
Beginning balance, Goodwill	$ 4,974,000,000	$ 4,622,000,000	$ 4,622,000,000
Adjustment to original purchase price allocation			337,000,000
Foreign currency translation adjustments	(30,000,000)		15,000,000
Transfers to assets held for sale	(57,000,000)
Ending balance, Goodwill	4,887,000,000		4,974,000,000
Goodwill impairments	0	0
Defense Solutions
Goodwill [Roll Forward]
Beginning balance, Goodwill	2,055,000,000	1,954,000,000	1,954,000,000
Adjustment to original purchase price allocation			94,000,000
Foreign currency translation adjustments	(25,000,000)		7,000,000
Transfers to assets held for sale	0
Ending balance, Goodwill	2,030,000,000		2,055,000,000
Civil
Goodwill [Roll Forward]
Beginning balance, Goodwill	1,998,000,000	1,731,000,000	1,731,000,000
Adjustment to original purchase price allocation			259,000,000
Foreign currency translation adjustments	(5,000,000)		8,000,000
Transfers to assets held for sale	(57,000,000)
Ending balance, Goodwill	1,936,000,000		1,998,000,000
Accumulated goodwill impairment losses	117,000,000		117,000,000	$ 117,000,000
Health
Goodwill [Roll Forward]
Beginning balance, Goodwill	921,000,000	$ 937,000,000	937,000,000
Adjustment to original purchase price allocation			(16,000,000)
Foreign currency translation adjustments	0		0
Transfers to assets held for sale	0
Ending balance, Goodwill	921,000,000		921,000,000
Accumulated goodwill impairment losses	$ 369,000,000		$ 369,000,000	$ 369,000,000

Intangible Assets (Summary) (De

Intangible Assets (Summary) (Details) - USD ($) $ in Millions	Jun. 29, 2018	Dec. 29, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying value	$ 1,098	$ 1,264
Accumulated amortization	(353)	(412)
Net carrying value	745	852
Total intangible assets, Gross carrying value	1,102	1,268
Total intangible assets, Net carrying value	749	856
Trade names
Acquired Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	4	4
Program and contract intangibles
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying value	1,005	1,013
Accumulated amortization	(281)	(187)
Net carrying value	724	826
Software and technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying value	89	89
Accumulated amortization	(68)	(64)
Net carrying value	21	25
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying value	4	4
Accumulated amortization	(4)	(3)
Net carrying value	0	1
Backlog
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying value	0	158
Accumulated amortization	0	(158)
Net carrying value	$ 0	$ 0

Intangible Assets (Narrative) (

Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 51	$ 67	$ 101	$ 136

Intangible Assets (Amortization

Intangible Assets (Amortization of Intangibles) (Details) - USD ($) $ in Millions	Jun. 29, 2018	Dec. 29, 2017
Estimated Annual Intangible Amortization Expense
2018 (remainder of year)	$ 100
2,019	170
2,020	126
2,021	105
2,022	92
2023 and thereafter	152
Net carrying value	$ 745	$ 852

Property, Plant and Equipment64

Property, Plant and Equipment (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 29, 2018	Mar. 30, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Dec. 29, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 550			$ 550		$ 546
Less: accumulated depreciation and amortization	(329)			(329)		(314)
Property, plant and equipment, net	221			221		232
Depreciation	15		$ 13	28	$ 26
Asset impairment charges	0		$ 0	7	$ 0
Computers and other equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	188			188		194
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	186			186		171
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	56			56		54
Office furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	35			35		34
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	40			40		49
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 45			$ 45		$ 44
Corporate
Property, Plant and Equipment [Line Items]
Asset impairment charges		$ 7

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 29, 2018	Mar. 30, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Dec. 29, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairment charges	$ 0		$ 0	$ 7,000,000	$ 0
Designated as Hedging Instrument | Secured Debt
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Hedged instrument, face amount	1,600,000,000			1,600,000,000
Asset Derivatives | Designated as Hedging Instrument | $450 million notes, due December 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Hedged instrument, face amount	$ 450,000,000			$ 450,000,000
Stated interest rate (in percentage)	4.45%			4.45%
Asset Derivatives | Designated as Hedging Instrument | $450 million notes, due December 2020 | Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Stated interest rate (in percentage)	4.45%			4.45%
Carrying value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	$ 55,000,000			$ 55,000,000		$ 37,000,000
Derivative liability	7,000,000			7,000,000		0
Fair value of notes receivable	63,000,000			63,000,000		63,000,000
Fair value of debt instrument	3,100,000,000			3,100,000,000		3,100,000,000
Fair value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	55,000,000			55,000,000		37,000,000
Derivative liability	7,000,000			7,000,000		0
Fair value of debt instrument	$ 3,100,000,000			$ 3,100,000,000		$ 3,200,000,000
Corporate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Asset impairment charges		$ 7,000,000

Derivative Instruments (Details

Derivative Instruments (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Feb. 28, 2018	Dec. 29, 2017
Derivative [Line Items]
Carrying amount of hedged item	$ 442,000,000		$ 442,000,000			$ 449,000,000
Cumulative amount of fair value adjustment included within the hedged item	(7,000,000)		(7,000,000)			0
Total interest expense, net presented in the condensed consolidated statements of income in which the effects of cash flow hedges are recorded	35,000,000	$ 34,000,000	69,000,000	$ 70,000,000
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	7,000,000	(4,000,000)	21,000,000	(3,000,000)
Gains expected to be reclassified in the next 12 months	15,000,000		15,000,000
Asset Derivatives | Designated as Hedging Instrument | $450 million notes, due December 2020
Derivative [Line Items]
Hedged instrument, face amount	$ 450,000,000		$ 450,000,000
Stated interest rate (in percentage)	4.45%		4.45%
Asset Derivatives | long term debt | Designated as Hedging Instrument | $450 million notes, due December 2020
Derivative [Line Items]
Hedged instrument, face amount	$ 450,000,000		$ 450,000,000
Stated interest rate (in percentage)	4.45%		4.45%
Cash Flow Hedging | Asset Derivatives | Other assets | Designated as Hedging Instrument
Derivative [Line Items]
Asset Derivatives	$ 55,000,000		$ 55,000,000			37,000,000
Fair Value Hedging | Asset Derivatives | Other long-term liabilities | Designated as Hedging Instrument
Derivative [Line Items]
Liability Derivatives	7,000,000		7,000,000			$ 0
Secured Debt | Designated as Hedging Instrument
Derivative [Line Items]
Hedged instrument, face amount	1,600,000,000		1,600,000,000
Secured Debt | Interest Rate Swap, Maturity Date December 2021 | Designated as Hedging Instrument
Derivative [Line Items]
Hedged instrument, face amount					$ 1,100,000,000
Stated interest rate (in percentage)					1.08%
Secured Debt | Interest Rate Swap, Maturity Date August 2022 | Designated as Hedging Instrument
Derivative [Line Items]
Hedged instrument, face amount					$ 300,000,000
Stated interest rate (in percentage)					1.66%
Secured Debt | Interest Rate Swap, Maturity Date August 2022 | Designated as Hedging Instrument | Variable Rate Loan
Derivative [Line Items]
Hedged instrument, face amount					$ 250,000,000
Stated interest rate (in percentage)					2.59%
Interest Expense
Derivative [Line Items]
Cash flow hedges, amount reclassified from accumulated other comprehensive income to interest expense, net	$ (2,000,000)	$ 0	$ (3,000,000)	$ 1,000,000

Debt (Summary of debt) (Detail)

Debt (Summary of debt) (Detail) - USD ($)	Jun. 29, 2018	Mar. 30, 2018	Dec. 29, 2017
Debt Instrument [Line Items]
Total long-term debt	$ 3,061,000,000		$ 3,111,000,000
Less: current portion	71,000,000		55,000,000
Total long-term debt, net of current portion	2,990,000,000		3,056,000,000
Capital leases and notes payable due on various dates through fiscal 2022
Debt Instrument [Line Items]
Capital leases and notes payable	$ 21,000,000		27,000,000
Minimum | Capital leases and notes payable due on various dates through fiscal 2022
Debt Instrument [Line Items]
Stated interest rate (in percentage)	0.00%
Maximum | Capital leases and notes payable due on various dates through fiscal 2022
Debt Instrument [Line Items]
Stated interest rate (in percentage)	5.55%
Secured Debt | $450 million notes, due December 2020
Debt Instrument [Line Items]
Senior secured notes	$ 442,000,000		449,000,000
Stated interest rate (in percentage)	4.45%
Effective interest rate	4.53%
Senior unsecured notes, face amount	$ 450,000,000
Secured Debt | $300 million notes, due December 2040
Debt Instrument [Line Items]
Senior secured notes	$ 216,000,000		216,000,000
Stated interest rate (in percentage)	5.95%
Effective interest rate	6.03%
Senior unsecured notes, face amount	$ 300,000,000
Secured Debt | $690 million Term Loan A, due August 2022
Debt Instrument [Line Items]
Senior secured term loans	$ 625,000,000		644,000,000
Stated interest rate (in percentage)	3.88%
Effective interest rate	4.38%
Senior unsecured notes, face amount	$ 690,000,000
Secured Debt | $310 million Term Loan A, due August 2022
Debt Instrument [Line Items]
Senior secured term loans	$ 262,000,000		270,000,000
Stated interest rate (in percentage)	3.88%
Effective interest rate	4.37%
Senior unsecured notes, face amount	$ 310,000,000
Secured Debt | $1,131 million Term Loan B, due August 2023
Debt Instrument [Line Items]
Senior secured term loans	$ 1,091,000,000		1,101,000,000
Stated interest rate (in percentage)	3.88%
Effective interest rate	4.26%
Senior unsecured notes, face amount	$ 1,131,000,000	$ 1,100,000,000
Unsecured Debt | $250 million notes, due July 2032
Debt Instrument [Line Items]
Senior unsecured notes	$ 246,000,000		246,000,000
Stated interest rate (in percentage)	7.13%
Effective interest rate	7.43%
Senior unsecured notes, face amount	$ 250,000,000
Unsecured Debt | $300 million notes, due July 2033
Debt Instrument [Line Items]
Senior unsecured notes	$ 158,000,000		$ 158,000,000
Stated interest rate (in percentage)	5.50%
Effective interest rate	5.88%
Senior unsecured notes, face amount	$ 300,000,000

Debt (Senior Secured Notes and

Debt (Senior Secured Notes and Senior Secured Term Loans) (Detail) - USD ($)	1 Months Ended		3 Months Ended		6 Months Ended
	Apr. 30, 2018	Mar. 30, 2018	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017	Dec. 29, 2017
Debt Instrument [Line Items]
Long-term debt			$ 3,088,000,000		$ 3,088,000,000		$ 3,129,000,000
Unamortized debt discounts and deferred debt issuances costs			41,000,000		41,000,000		$ 45,000,000
Amortization of debt issuance costs			3,000,000	$ 3,000,000	6,000,000	$ 7,000,000
Secured Debt
Debt Instrument [Line Items]
Repayment of debt, quarterly			16,000,000	21,000,000	31,000,000	$ 41,000,000
Repayments of debt	$ 10,000,000			$ 25,000,000
Secured Debt | $1,131 million Term Loan B, due August 2023
Debt Instrument [Line Items]
Note payable, face amount		$ 1,100,000,000	$ 1,131,000,000		$ 1,131,000,000
Decrease in basis points		25.00%
London Interbank Offered Rate (LIBOR) | Secured Debt | Term Loan B
Debt Instrument [Line Items]
Variable rate (in percentage)		1.75%			1.75%
London Interbank Offered Rate (LIBOR) | Secured Debt | Term Loan A
Debt Instrument [Line Items]
Variable rate (in percentage)					1.75%
Minimum | London Interbank Offered Rate (LIBOR) | Secured Debt | Term Loan A
Debt Instrument [Line Items]
Variable rate (in percentage)			1.50%
Maximum | London Interbank Offered Rate (LIBOR) | Secured Debt | Term Loan A
Debt Instrument [Line Items]
Variable rate (in percentage)			2.00%
Fair Value Hedging | Designated as Hedging Instrument | Asset Derivatives
Debt Instrument [Line Items]
Derivative liability			$ 7,000,000		$ 7,000,000

Debt (Revolving Credit Facility

Debt (Revolving Credit Facility) (Detail) - Line of Credit - Revolving Credit Facility - USD ($)	Jun. 29, 2018	Dec. 29, 2017
Debt Instrument [Line Items]
Outstanding credit facility	$ 0	$ 0
Unsecured borrowing capacity	$ 750,000,000

Accumulated Other Comprehensi70

Accumulated Other Comprehensive Income (Schedule of Accumulated Other Comprehensive Loss) (Detail) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 29, 2018	Dec. 29, 2017	Dec. 30, 2017
AOCI, Net of Tax [Roll Forward]
Beginning balance	$ 3,370
Cumulative adjustments related to ASU adoptions (Note 2)			$ 1
Ending balance	3,416	$ 3,370
Total accumulated other comprehensive income
AOCI, Net of Tax [Roll Forward]
Beginning balance	33	(4)
Cumulative adjustments related to ASU adoptions (Note 2)			9
Other comprehensive (loss) income	(17)	55
Taxes	1	(18)
Reclassification from accumulated other comprehensive income	(3)
Ending balance	23	33
Foreign currency translation adjustments
AOCI, Net of Tax [Roll Forward]
Beginning balance	17	(7)
Cumulative adjustments related to ASU adoptions (Note 2)			3
Other comprehensive (loss) income	(38)	36
Taxes	5	(12)
Reclassification from accumulated other comprehensive income	0
Ending balance	(13)	17
Unrecognized gain on derivative instruments
AOCI, Net of Tax [Roll Forward]
Beginning balance	14	10
Cumulative adjustments related to ASU adoptions (Note 2)			10
Other comprehensive (loss) income	21	10
Taxes	(4)	(6)
Reclassification from accumulated other comprehensive income	(3)
Ending balance	38	14
Pension adjustments
AOCI, Net of Tax [Roll Forward]
Beginning balance	2	(7)
Cumulative adjustments related to ASU adoptions (Note 2)			$ (4)
Other comprehensive (loss) income	0	9
Taxes	0	0
Reclassification from accumulated other comprehensive income	0
Ending balance	$ (2)	$ 2

Earnings Per Share (EPS) (Recon

Earnings Per Share (EPS) (Reconciliation of Weighted Average Number of Shares Outstanding) (Detail) - shares shares in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Earnings Per Share [Abstract]
Basic weighted average number of shares outstanding (shares)	152	151	152	151
Dilutive common share equivalents-stock options and other stock awards (shares)	2	2	2	2
Diluted weighted average number of shares outstanding (shares)	154	153	154	153

Earnings Per Share (EPS) (Narra

Earnings Per Share (EPS) (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 29, 2018	Jun. 29, 2018
Earnings Per Share [Abstract]
Payments for repurchase of common stock	$ 90	$ 100

Supplementary Cash Flow Infor73

Supplementary Cash Flow Information and Restricted Cash (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Dec. 29, 2017	Dec. 30, 2016
Supplementary cash flow information:
Cash paid for interest	$ 68	$ 59
Cash paid for income taxes, net of refunds	55	107
Non-cash financing activity:
Purchase of non-controlling interests	7	0
Capital lease obligation	0	6
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents
Cash and cash equivalents	390
Restricted cash	20		$ 32
Total cash, cash equivalents and restricted cash	$ 323	$ 287	$ 422	$ 396

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate	12.10%	27.40%	14.80%	29.20%

Business Segments (Schedule of

Business Segments (Schedule of Segment Reporting Information by Segment) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Revenues	$ 2,529	$ 2,571	$ 4,972	$ 5,151
Operating income (loss)	199	166	358	307
Defense Solutions
Segment Reporting Information [Line Items]
Revenues	1,256		2,434
Civil
Segment Reporting Information [Line Items]
Revenues	822		1,662
Health
Segment Reporting Information [Line Items]
Revenues	451		876
Operating Segments | Defense Solutions
Segment Reporting Information [Line Items]
Revenues	1,256	1,243	2,434	2,537
Operating income (loss)	93	63	178	142
Operating Segments | Civil
Segment Reporting Information [Line Items]
Revenues	822	875	1,662	1,717
Operating income (loss)	61	66	135	120
Operating Segments | Health
Segment Reporting Information [Line Items]
Revenues	451	454	876	897
Operating income (loss)	68	74	110	121
Corporate
Segment Reporting Information [Line Items]
Revenues	0	(1)	0	0
Operating income (loss)	$ (23)	$ (37)	$ (65)	$ (76)

Contingencies (Additional Infor

Contingencies (Additional Information) (Detail) € in Millions, $ in Millions	Apr. 10, 2018USD ($)	Sep. 29, 2017USD ($)	Apr. 30, 2012LegalMatter	Jun. 29, 2018USD ($)	Nov. 10, 2015USD ($)	Dec. 31, 2013EUR (€)
Securities Class Actions
Legal Proceedings [Line Items]
Number of lawsuits | LegalMatter			3
Number of lawsuits, withdrawn | LegalMatter			1
Number of lawsuits, consolidated | LegalMatter			2
Greek Government Contract
Legal Proceedings [Line Items]
Arbitral award | €						€ 39
MSA Venture
Legal Proceedings [Line Items]
Estimate of possible loss				$ 64	$ 64
Loss Contingency, Estimate of Possible Loss, Amount Deferred				32
Contingency accrual				$ 39
Lockheed Martin | MSA Venture
Legal Proceedings [Line Items]
Percentage of damages covered, between $38 million and $64 million (percentage)				100.00%
Percentage of damages covered, excess of $64 million settlement amount (percentage)				50.00%
Leidos
Legal Proceedings [Line Items]
Litigation settlement, percentage of total (percentage)				25.00%
Leidos | MSA Venture
Legal Proceedings [Line Items]
Estimate of possible loss				$ 38
Virnet X Inc
Legal Proceedings [Line Items]
Amount awarded to other party, pre interest		$ 343
Awarded to the other party, interest and legal fees		96
Amount awarded to other party	$ 502	$ 439
Information Systems & Global Solutions Business of Lockheed Martin | MSA Venture
Legal Proceedings [Line Items]
Indemnification asset				$ 1

Commitments (Additional Informa

Commitments (Additional Information) (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 29, 2018	Jan. 24, 2018
Other Commitments And Contingencies [Line Items]
Operating lease, term of contract (months)		148 months
Rent for first year		$ 11
Operating lease, rent increase, percentage		2.50%
Standby Letters of Credit
Other Commitments And Contingencies [Line Items]
Amount outstanding	$ 93
Performance Guarantee
Other Commitments And Contingencies [Line Items]
Surety bonds	$ 123
Standby Letters of Credit and Surety Bonds
Other Commitments And Contingencies [Line Items]
Debt instrument term	4 years

Uncategorized Items - ldos-2018

Label	Element	Value
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	$ 3,384,000,000
AOCI Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent	us-gaap_StockholdersEquity	42,000,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	42,000,000
Noncontrolling Interest [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	13,000,000
Retained Earnings [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	(15,000,000)
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	(8,000,000)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Stockholders' Equity Attributable to Parent	us-gaap_StockholdersEquity	24,000,000
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent	us-gaap_StockholdersEquity	$ 20,000,000
Common Stock [Member]
Shares, Issued	us-gaap_SharesIssued	151,000,000
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent	us-gaap_StockholdersEquity	$ (2,000,000)
Additional Paid-in Capital [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	3,344,000,000
Parent [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Adjusted Balance	us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	3,371,000,000
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 1,000,000