Leidos (LDOS) 10-Q 4 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 30, 2018	Apr. 24, 2018
Document Documentand Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
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		151,785,398

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 30, 2018	Dec. 29, 2017
Current assets:
Cash and cash equivalents	$ 215	$ 390
Receivables, net	1,914	1,831
Inventory, prepaid expenses and other current assets	506	453
Total current assets	2,635	2,674
Property, plant and equipment, net	227	232
Intangible assets, net	806	856
Goodwill	4,976	4,974
Other assets	269	254
Total assets	8,913	8,990
Current liabilities:
Accounts payable and accrued liabilities	1,622	1,639
Accrued payroll and employee benefits	379	487
Dividends payable	14	17
Income taxes payable	7	4
Long-term debt, current portion	81	55
Total current liabilities	2,103	2,202
Long-term debt, net of current portion	3,007	3,056
Deferred tax liabilities	221	220
Other long-term liabilities	148	129
Commitments and contingencies (Notes 20 and 21)
Stockholders’ equity:
Common stock, $.0001 par value, 500 million shares authorized, 152 million and 151 million shares issued and outstanding at March 30, 2018 and December 29, 2017, respectively	0	0
Additional paid-in capital	3,338	3,344
Accumulated earnings (deficit)	37	(7)
Accumulated other comprehensive income	56	33
Total Leidos stockholders’ equity	3,431	3,370
Non-controlling interest	3	13
Total equity	3,434	3,383
Total liabilities and stockholders' equity	$ 8,913	$ 8,990

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Mar. 30, 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	152,000,000	151,000,000
Common stock, shares outstanding	152,000,000	151,000,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017
Income Statement [Abstract]
Revenues	$ 2,443	$ 2,580
Cost of revenues	2,086	2,233
Selling, general and administrative expenses	178	181
Acquisition and integration costs	11	19
Asset impairment charges	7	0
Restructuring expenses	6	13
Equity earnings of non-consolidated subsidiaries	(4)	(7)
Operating income	159	141
Interest expense, net	(34)	(36)
Other income, net	0	3
Income before income taxes	125	108
Income tax expense	(23)	(34)
Net income	102	74
Less: net income attributable to non-controlling interest	0	2
Net income attributable to Leidos common stockholders	$ 102	$ 72
Earnings per share:
Basic (dollars per share)	$ 0.67	$ 0.48
Diluted (dollars per share)	0.66	0.47
Cash dividends declared per share (dollars per share)	$ 0.32	$ 0.32

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 102	$ 74
Other comprehensive income, net of taxes:
Foreign currency translation adjustments	4	11
Unrecognized gain on derivative instruments (Note 15)	10	1
Total other comprehensive income, net of taxes	14	12
Comprehensive income	116	86
Less: comprehensive income attributable to non-controlling interest	0	2
Comprehensive income attributable to Leidos common stockholders	$ 116	$ 84

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	74	72			72		2
Other comprehensive income, net of taxes	12	12				12
Issuances of stock			1
Issuances of stock	3	3		3
Repurchases of stock and other	(6)	(6)		(6)
Dividends declared	(49)	(49)			(49)
Stock-based compensation	10	10		10
Adjustment to original purchase price allocation	(3)						(3)
Balance (shares) at Mar. 31, 2017			151
Balance at Mar. 31, 2017	3,188	3,177		3,323	(154)	8	11
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative adjustments related to ASU adoptions	1	1			(8)	9
Adjusted balance	3,384	3,371		3,344	(15)	42	13
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	102	102			102
Other comprehensive income, net of taxes	14	14				14
Issuances of stock			1
Issuances of stock	5	5		5
Repurchases of stock and other	(22)	(22)		(22)
Dividends declared	(50)	(50)			(50)
Stock-based compensation	11	11		11
Purchase of non-controlling interests	(10)						(10)
Balance (shares) at Mar. 30, 2018			152
Balance at Mar. 30, 2018	$ 3,434	$ 3,431		$ 3,338	$ 37	$ 56	$ 3

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017
Cash flows from operations:
Net income	$ 102	$ 74
Adjustments to reconcile net income to net cash provided by (used in) operations:
Depreciation and amortization	63	82
Stock-based compensation	11	10
Asset impairment charges	7	0
Other	7	3
Change in assets and liabilities, net of effects of acquisitions and dispositions:
Receivables	(84)	(190)
Inventory, prepaid expenses and other current assets	(63)	22
Accounts payable and accrued liabilities	60	(37)
Accrued payroll and employee benefits	(107)	(86)
Deferred income taxes and income taxes receivable/payable	28	31
Other long-term assets/liabilities	(2)	20
Net cash provided by (used in) operating activities	22	(71)
Cash flows from investing activities:
Payments for property, plant and equipment	(15)	(7)
Acquisitions of businesses	(81)	0
Other	0	2
Net cash used in investing activities	(96)	(5)
Cash flows from financing activities:
Payments of long-term debt	(17)	(22)
Proceeds from issuances of stock	4	1
Repurchases of stock and other	(22)	(6)
Dividend payments	(52)	(50)
Other	(4)	(1)
Net cash used in financing activities	(91)	(78)
Net decrease in cash, cash equivalents and restricted cash	(165)	(154)
Cash, cash equivalents and restricted cash at beginning of period	422	396
Cash, cash equivalents and restricted cash at end of period	$ 257	$ 242

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 30, 2018
Accounting Policies [Abstract]
Nature of Operations and Basis of Presentation	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% effective January 26, 2018. The Company has consolidated 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 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, $37 million was reclassified from "Cost of revenues" to "Selling, general and administrative expenses" on the condensed consolidated statement of income for the quarter ended March 31, 2017 . The Company aggregated "Interest income" and "Interest expense" into "Interest expense, net" on the Company's condensed consolidated statements of income. Due to the adoption of 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 quarter ended March 31, 2017 , increased by $16 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, for the quarter ended March 31, 2017, 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.

Accounting Standards

Accounting Standards	3 Months Ended
	Mar. 30, 2018
Accounting Changes and Error Corrections [Abstract]
Accounting Standards	Accounting Standards Accounting Standards Updates Adopted ASU 2014-09, Revenue from Contracts with Customers (Topic 606) In May 2014, the FASB issued Accounting Standards Update ("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 that 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 provides 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 is effective for annual reporting periods beginning after December 15, 2017. Effective December 30, 2017 (beginning of fiscal year 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 of the new standard was on certain of the Company’s units-of-delivery contracts, on which the Company previously recognized revenue at a point in time and under ASC 606 are 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 substantial majority 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 transfered 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 in the first quarter of fiscal 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 in the Tax Act is recognized. Early adoption is permitted. The Company early adopted the provisions of ASU 2018-02 in the first quarter of 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 corporate 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 to be 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, Leases (Topic 842) In February 2016, the FASB issued ASU 2016-02, which supersedes the current lease guidance under ASC 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 reporting periods beginning after December 15, 2018, and should be adopted under the modified retrospective approach. Early adoption is permitted. The Company is in the process of evaluating the provisions of ASU 2016-02 and its impact on the Company's condensed consolidated financial position, results of operations and cash flows.

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 30, 2018
Accounting Policies [Abstract]
Significant Accounting Policies	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 ("CPFF"), 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 the 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 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 an 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 none of the Company's contracts contain a significant financing component, which would require an adjustment to the transaction price of the contract. The Company recognizes revenue on its services 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. 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, sub-contract 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 good 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 ("the 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 March 30, March 31, (in millions, except per share amounts) Net favorable impact to income before income taxes $ 35 $ 22 Impact on diluted EPS attributable to Leidos common stockholders $ 0.17 $ 0.09 The impact on diluted EPS attributable to Leidos common stockholders is calculated using the Company's statutory tax rate. During the quarter ended March 30, 2018 , revenue recognized from performance obligations satisfied in previous periods was $34 million . The change in estimates primarily relate to revision of variable consideration including award fees and revisions to estimates at completion adjustments resulting from change in contract scope or due to true-up 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 March 30, 2018 , and December 29, 2017, the Company included $124 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 are deferred and included within "Accounts payable and accrued liabilities" or "Other long-term liabilities" on the condensed consolidated balance sheets.

Revenue

Revenue	3 Months Ended
	Mar. 30, 2018
Revenue from Contract with Customer [Abstract]
Revenue	Revenue Dual Reporting The effects to the condensed consolidated financial statements at March 30, 2018 , as a result of applying ASC 606, rather than previous GAAP ("ASC 605"), are the following: As Reported (ASC 606) As Adjusted (ASC 605) (in millions) Balance sheet: Receivables, net $ 1,914 $ 1,909 Inventory, prepaid expenses and other current assets 506 509 Accumulated earnings (deficit) 37 35 Income statement: Revenues $ 2,443 $ 2,438 Cost of revenues 2,086 2,083 Operating income 159 157 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 indefinite delivery/indefinite quantity contracts. As of March 30, 2018 , the Company had $8.9 billion of remaining performance obligations, which are expected to be recognized as revenue in the amounts of $5.3 billion , $1.2 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 revenue by customer-type, contract-type and geographic location for each of its reportable segments. These categories represent how the nature, timing and uncertainty of revenue and cash flows are affected by the U.S. government procurement environment. Disaggregated revenue by customer-type was as follows: Three Months Ended March 30, 2018 Defense Solutions Civil Health Total (in millions) DoD $ 1,032 $ 23 $ 92 $ 1,147 Other government agencies (1) 45 589 298 932 Commercial and non-U.S. customers 101 228 35 364 Total $ 1,178 $ 840 $ 425 $ 2,443 (1) Includes non-DoD federal government agencies, state and local government agencies. The majority of the Company’s revenue is generated from U.S. government contracts, either as a prime contractor or as a subcontractor to other contractors. Revenue 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 DoD may be impacted by spending priorities as a result of competing demands for federal funds. Disaggregated revenue by contract-type was as follows: Three Months Ended March 30, 2018 Defense Solutions Civil Health Total (in millions) Cost-reimbursement and fixed-price-incentive- fee $ 771 $ 439 $ 50 $ 1,260 Firm-fixed-price 283 256 253 792 Time-and-materials and fixed-price-level-of-effort 124 145 122 391 Total $ 1,178 $ 840 $ 425 $ 2,443 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 revenue by geographic location was as follows: Three Months Ended March 30, 2018 Defense Solutions Civil Health Total (in millions) United States $ 1,088 $ 696 $ 425 $ 2,209 International 90 144 — 234 Total $ 1,178 $ 840 $ 425 $ 2,443 The Company’s international business operations is 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. Contract Assets and Liabilities Contract assets include unbilled receivables, which is the amount of revenue recognized that exceeds the amount billed to the customer, and right to payment is not just subject to the passage of time. Contract assets also include transition costs and project assets where under certain services contracts, costs are incurred, usually at the beginning of the contract performance, to transition the services, employees and equipment from the customer or assets capitalized for specific contracts where delivery has not yet occurred. Contract liabilities consist of deferred revenue. The components of contract assets and contract liabilities consisted of the following: Balance sheet line item March 30, December 30, 2017 (1) (in millions) Contract assets - current: Unbilled receivables (2) Receivables, net $ 836 $ 844 Transition costs and project assets Inventory, prepaid expenses and other current assets 114 59 $ 950 $ 903 Contract assets - non-current: Transition costs and project assets Other assets $ 14 $ 13 Contract liabilities - current: Deferred revenue Accounts payable and accrued liabilities $ 406 $ 293 Contract liabilities - non-current: Deferred revenue Other long-term liabilities $ 22 $ 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 (ASC 606) . (2) Balances exclude $459 million and $234 million determined to be billable at March 30, 2018, and December 30, 2017, respectively. The increase in "Contract assets - current" was primarily due to the timing of billings and revenue recognized on certain contracts. The increase also relates to project assets on certain contracts. The increase in "Contract liabilities- current" was primarily due to advance payments received on a certain contract. During the quarter ended March 30, 2018 , the Company recognized revenue of $55 million relating to amounts that were included as a contract liability at December 30, 2017 . During the quarter ended March 30, 2018 , the Company recognized $3 million of amortization related to its transition costs and project assets. The Company did not recognize any impairment losses on contract assets for the quarter ended March 30, 2018 .

Contract Asset and Liabilities

Contract Asset and Liabilities	3 Months Ended
	Mar. 30, 2018
Revenue from Contract with Customer [Abstract]
Contract Asset and Liabilities	Revenue Dual Reporting The effects to the condensed consolidated financial statements at March 30, 2018 , as a result of applying ASC 606, rather than previous GAAP ("ASC 605"), are the following: As Reported (ASC 606) As Adjusted (ASC 605) (in millions) Balance sheet: Receivables, net $ 1,914 $ 1,909 Inventory, prepaid expenses and other current assets 506 509 Accumulated earnings (deficit) 37 35 Income statement: Revenues $ 2,443 $ 2,438 Cost of revenues 2,086 2,083 Operating income 159 157 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 indefinite delivery/indefinite quantity contracts. As of March 30, 2018 , the Company had $8.9 billion of remaining performance obligations, which are expected to be recognized as revenue in the amounts of $5.3 billion , $1.2 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 revenue by customer-type, contract-type and geographic location for each of its reportable segments. These categories represent how the nature, timing and uncertainty of revenue and cash flows are affected by the U.S. government procurement environment. Disaggregated revenue by customer-type was as follows: Three Months Ended March 30, 2018 Defense Solutions Civil Health Total (in millions) DoD $ 1,032 $ 23 $ 92 $ 1,147 Other government agencies (1) 45 589 298 932 Commercial and non-U.S. customers 101 228 35 364 Total $ 1,178 $ 840 $ 425 $ 2,443 (1) Includes non-DoD federal government agencies, state and local government agencies. The majority of the Company’s revenue is generated from U.S. government contracts, either as a prime contractor or as a subcontractor to other contractors. Revenue 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 DoD may be impacted by spending priorities as a result of competing demands for federal funds. Disaggregated revenue by contract-type was as follows: Three Months Ended March 30, 2018 Defense Solutions Civil Health Total (in millions) Cost-reimbursement and fixed-price-incentive- fee $ 771 $ 439 $ 50 $ 1,260 Firm-fixed-price 283 256 253 792 Time-and-materials and fixed-price-level-of-effort 124 145 122 391 Total $ 1,178 $ 840 $ 425 $ 2,443 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 revenue by geographic location was as follows: Three Months Ended March 30, 2018 Defense Solutions Civil Health Total (in millions) United States $ 1,088 $ 696 $ 425 $ 2,209 International 90 144 — 234 Total $ 1,178 $ 840 $ 425 $ 2,443 The Company’s international business operations is 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. Contract Assets and Liabilities Contract assets include unbilled receivables, which is the amount of revenue recognized that exceeds the amount billed to the customer, and right to payment is not just subject to the passage of time. Contract assets also include transition costs and project assets where under certain services contracts, costs are incurred, usually at the beginning of the contract performance, to transition the services, employees and equipment from the customer or assets capitalized for specific contracts where delivery has not yet occurred. Contract liabilities consist of deferred revenue. The components of contract assets and contract liabilities consisted of the following: Balance sheet line item March 30, December 30, 2017 (1) (in millions) Contract assets - current: Unbilled receivables (2) Receivables, net $ 836 $ 844 Transition costs and project assets Inventory, prepaid expenses and other current assets 114 59 $ 950 $ 903 Contract assets - non-current: Transition costs and project assets Other assets $ 14 $ 13 Contract liabilities - current: Deferred revenue Accounts payable and accrued liabilities $ 406 $ 293 Contract liabilities - non-current: Deferred revenue Other long-term liabilities $ 22 $ 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 (ASC 606) . (2) Balances exclude $459 million and $234 million determined to be billable at March 30, 2018, and December 30, 2017, respectively. The increase in "Contract assets - current" was primarily due to the timing of billings and revenue recognized on certain contracts. The increase also relates to project assets on certain contracts. The increase in "Contract liabilities- current" was primarily due to advance payments received on a certain contract. During the quarter ended March 30, 2018 , the Company recognized revenue of $55 million relating to amounts that were included as a contract liability at December 30, 2017 . During the quarter ended March 30, 2018 , the Company recognized $3 million of amortization related to its transition costs and project assets. The Company did not recognize any impairment losses on contract assets for the quarter ended March 30, 2018 .

Acquisitions

Acquisitions	3 Months Ended
	Mar. 30, 2018
Business Combinations [Abstract]
Acquisitions	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 recorded as cash flows from operating and investing activities, respectively, in the Company's condensed consolidated statements of cash flows. The Company incurred the following expenses related to the acquisition and integration of the IS&GS Business: Three Months Ended March 30, March 31, (in millions) Acquisition costs $ — $ 1 Integration costs 11 18 Total acquisition and integration costs $ 11 $ 19

Divestitures

Divestitures	3 Months Ended
	Mar. 30, 2018
Discontinued Operations and Disposal Groups [Abstract]
Divestitures	Divestitures 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 statements of income. On February 28, 2018, Leidos and Plainfield entered into an amendment to the Note, allowing Plainfield to defer the principal and accrued interest payments due until the earlier of April 28, 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 April 28, 2018, Leidos shall allow Plainfield to settle the Note in full for $40 million plus 50% of additional net proceeds obtained by Plainfield.

Restructuring Expenses

Restructuring Expenses	3 Months Ended
	Mar. 30, 2018
Restructuring and Related Activities [Abstract]
Restructuring Expenses	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 March 30, March 31, (in millions) Severance costs $ 1 $ 10 Lease termination expenses 5 3 Restructuring expenses related to the IS&GS Business $ 6 $ 13 As of March 30, 2018 , Leidos has recognized a total of $55 million of expense in connection with these restructuring activities. These restructuring expenses have been recorded within Corporate and presented separately 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 5 6 Cash payments (4 ) (4 ) (8 ) Balance as of March 30, 2018 $ 2 $ 5 $ 7 The Company expects the remainder of the restructuring liability to be substantially settled within one year .

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	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 on a recurring basis at fair value consisted of the following: March 30, 2018 December 29, 2017 Carrying value Fair value Carrying value Fair value (in millions) Financial assets: Derivatives $ 51 $ 51 $ 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 March 30, 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 March 30, 2018 , and December 29, 2017, the fair value of debt was $3.2 billion and the carrying amount was $3.1 billion (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). As of March 30, 2018 , the Company had a real estate property measured at fair value (Level 2) (see "Note 12–Property, Plant and Equipment"). The Company did not have any assets or liabilities measured at fair value on a non-recurring basis using Level 3 inputs at March 30, 2018 .

Goodwill

Goodwill	3 Months Ended
	Mar. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	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 (6 ) 8 — 2 Goodwill at March 30, 2018 $ 2,049 $ 2,006 $ 921 $ 4,976 Accumulated goodwill impairment losses were $369 million and $117 million within the Health and Civil segments, respectively, at March 30, 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 quarters ended March 30, 2018 , and March 31, 2017 .

Intangible Assets

Intangible Assets	3 Months Ended
	Mar. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Intangible Assets Intangible assets consisted of the following: March 30, 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 $ 1,013 $ (235 ) $ 778 $ 1,013 $ (187 ) $ 826 Software and technology 89 (66 ) 23 89 (64 ) 25 Customer relationships 4 (3 ) 1 4 (3 ) 1 Backlog — — — 158 (158 ) — Total finite-lived intangible assets 1,106 (304 ) 802 1,264 (412 ) 852 Indefinite-lived intangible assets: Trade names 4 — 4 4 — 4 Total intangible assets $ 1,110 $ (304 ) $ 806 $ 1,268 $ (412 ) $ 856 Amortization expense related to intangible assets was $50 million and $69 million for the quarter ended March 30, 2018 , and March 31, 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 March 30, 2018 , was as follows: Fiscal Year Ending (in millions) 2018 (remainder of year) $ 151 2019 173 2020 128 2021 106 2022 92 2023 and thereafter 152 $ 802

Property, Plant and Equipment

Property, Plant and Equipment	3 Months Ended
	Mar. 30, 2018
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment, net consisted of the following: March 30, December 29, (in millions) Computers and other equipment $ 196 $ 194 Leasehold improvements 172 171 Buildings and improvements 56 54 Office furniture and fixtures 34 34 Land 40 49 Construction in progress 55 44 553 546 Less: accumulated depreciation and amortization (326 ) (314 ) $ 227 $ 232 Depreciation expense was $13 million for each of the quarters ended March 30, 2018, and March 31, 2017. 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.

Derivative Instruments

Derivative Instruments	3 Months Ended
	Mar. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	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 March 30, December 29, (in millions) Cash flow interest rate swaps Other assets 51 37 Liability Derivatives Balance sheet line item March 30, December 29, (in millions) Fair value interest rate swaps Other long-term liabilities $ 6 $ — Cash flow interest rate swaps Other long-term liabilities 1 — $ 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 March 30, December 29, March 30, December 29, (in millions) Long-term debt, net of current portion $ 443 $ 449 $ (6 ) $ — 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 will be 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 March 30, March 31, (in millions) Total interest expense, net presented in the condensed consolidated statements of income in which the effects of cash flow hedges are recorded $ 34 $ 36 Amount recognized in other comprehensive income 14 1 Amount reclassified from accumulated other comprehensive income to interest expense, net (1 ) 1 The Company expects to reclassify gains of $11 million from accumulated other comprehensive income into earnings during the next 12 months.

Debt

Debt	3 Months Ended
	Mar. 30, 2018
Debt Disclosure [Abstract]
Debt	Debt The Company's debt consisted of the following: Stated interest rate Effective interest rate March 30, 2018 (1) December 29, 2017 (1) (in millions) Senior secured notes: $450 million notes, due December 2020 4.45% 4.53% $ 443 $ 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 3.69% 4.18% 636 644 $310 million Term Loan A, due August 2022 3.69% 4.18% 267 270 $1,131 million Term Loan B, due August 2023 3.69% 4.07% 1,098 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 24 27 Total long-term debt 3,088 3,111 Less: current portion 81 55 Total long-term debt, net of current portion $ 3,007 $ 3,056 (1) The carrying amounts of the senior secured term loans and notes and unsecured notes as of March 30, 2018 , and December 29, 2017 , include the remaining principal outstanding of $3,114 million and $3,129 million , respectively, less total unamortized debt discounts and deferred debt issuances costs of $44 million and $45 million , respectively, less $6 million related to the fair value of the interest rate swaps (see "Note 13–Derivative Instruments") as of March 30, 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 March 30, 2018 , the current margin on Term Loan A and Term Loan B was 1.75% . During the quarter ended March 30, 2018 , and March 31, 2017 , the Company made $15 million and $20 million , respectively, of required quarterly payments on its senior secured term loans. 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 March 30, 2018 , and December 29, 2017 , there were no borrowings outstanding under the credit facility. 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 March 30, 2018 .

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	3 Months Ended
	Mar. 30, 2018
Equity [Abstract]
Accumulated Other Comprehensive Income	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 income 3 14 — 17 Taxes 1 (3 ) — (2 ) Reclassification from accumulated other comprehensive income — (1 ) — (1 ) Balance at March 30, 2018 $ 24 $ 34 $ (2 ) $ 56 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)	3 Months Ended
	Mar. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share (EPS)	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 March 30, March 31, (in millions) Basic weighted average number of shares outstanding 152 150 Dilutive common share equivalents—stock options and other stock awards 2 3 Diluted weighted average number of shares outstanding 154 153 During the quarter ended March 30, 2018, the Company made open market repurchases of its common stock for an aggregate purchase price of $10 million . All shares repurchased were immediately retired.

Supplementary Cash Flow Informa

Supplementary Cash Flow Information and Restricted Cash	3 Months Ended
	Mar. 30, 2018
Supplemental Cash Flow Information [Abstract]
Supplementary Cash Flow Information and Restricted Cash	Supplementary Cash Flow Information and Restricted Cash Supplementary cash flow information, and non-cash activities, for the periods presented was as follows: Three Months Ended March 30, March 31, (in millions) Supplementary cash flow information: Cash paid for interest $ 32 $ 32 Cash paid for income taxes, net of refunds 2 1 Non-cash financing activity: Capital lease obligation — 6 Purchase of non-controlling interests 7 — 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: March 30, December 29, (in millions) Cash and cash equivalents $ 215 $ 390 Restricted cash 42 32 Total cash, cash equivalents and restricted cash $ 257 $ 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 advances from customers that are restricted as to use for certain expenditures related to that customer's contract.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	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 March 30, 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 quarter ended March 30, 2018. For the quarter ended March 30, 2018 , the effective tax rate was 18.4% compared to 31.5% for the quarter ended March 31, 2017 . The decrease in the effective tax rate was primarily due to the Tax Act's reduction of the U.S. federal statutory rate.

Business Segments

Business Segments	3 Months Ended
	Mar. 30, 2018
Segment Reporting [Abstract]
Business Segments	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 March 30, March 31, (in millions) Revenues: Defense Solutions $ 1,178 $ 1,294 Civil 840 842 Health 425 443 Corporate — 1 Total revenues $ 2,443 $ 2,580 Operating income (loss): Defense Solutions $ 85 $ 79 Civil 74 54 Health 42 47 Corporate (42 ) (39 ) Total operating income $ 159 $ 141 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 on the condensed consolidated statements of income. Asset information by segment is not a key measure of performance used by the CODM.

Contingencies

Contingencies	3 Months Ended
	Mar. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Contingencies	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 that demand, pending resolution of the appeal, but to date the demand has not been rescinded. MSA and the other members 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 March 30, 2018 , the Company has 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 the first half of 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 or $48 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 in the amount of $63 million . 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 sought to annul the award through separate litigation in the Greek courts; however, on July 27, 2017, the Athens Court of Appeals issued a decision rejecting the government's position. 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 March 30, 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 2012 and subsequent years for the Company. 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 March 30, 2018 , the Company believes it has adequately reserved for potential adjustments from audits or reviews of contract costs.

Commitments

Commitments	3 Months Ended
	Mar. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments	Commitments The Company has outstanding letters of credit of $93 million as of March 30, 2018 , principally related to performance guarantees on contracts. The Company also has outstanding surety bonds with net exposure of $137 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	3 Months Ended
	Mar. 30, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events 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. On April 27, 2018, Leidos and Plainfield entered into an amendment to the Note, allowing Plainfield to defer the principal and accrued interest payments due until the earlier of May 31, 2018, or the date Plainfield successfully closes on a refinancing agreement with a third party.

Significant Accounting Polici30

Significant Accounting Policies Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 30, 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 ("CPFF"), 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 the 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 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 an 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 none of the Company's contracts contain a significant financing component, which would require an adjustment to the transaction price of the contract. The Company recognizes revenue on its services 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. 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, sub-contract 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 good 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").
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 are deferred and included within "Accounts payable and accrued liabilities" or "Other long-term liabilities" on the condensed consolidated balance sheets.
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 ("the IS&GS Business") (see "Note 6–Acquisitions"), where the adjustment is made for the period commencing from the date of acquisition.

Accounting Standards (Tables)

Accounting Standards (Tables)	3 Months Ended
	Mar. 30, 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 March 30, 2018 , as a result of applying ASC 606, rather than previous GAAP ("ASC 605"), are the following: As Reported (ASC 606) As Adjusted (ASC 605) (in millions) Balance sheet: Receivables, net $ 1,914 $ 1,909 Inventory, prepaid expenses and other current assets 506 509 Accumulated earnings (deficit) 37 35 Income statement: Revenues $ 2,443 $ 2,438 Cost of revenues 2,086 2,083 Operating income 159 157

Significant Accounting Polici32

Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 30, 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 March 30, March 31, (in millions, except per share amounts) Net favorable impact to income before income taxes $ 35 $ 22 Impact on diluted EPS attributable to Leidos common stockholders $ 0.17 $ 0.09

Revenue (Tables)

Revenue (Tables)	3 Months Ended
	Mar. 30, 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 March 30, 2018 , as a result of applying ASC 606, rather than previous GAAP ("ASC 605"), are the following: As Reported (ASC 606) As Adjusted (ASC 605) (in millions) Balance sheet: Receivables, net $ 1,914 $ 1,909 Inventory, prepaid expenses and other current assets 506 509 Accumulated earnings (deficit) 37 35 Income statement: Revenues $ 2,443 $ 2,438 Cost of revenues 2,086 2,083 Operating income 159 157
Schedule of disaggregated revenue	Disaggregated revenue by contract-type was as follows: Three Months Ended March 30, 2018 Defense Solutions Civil Health Total (in millions) Cost-reimbursement and fixed-price-incentive- fee $ 771 $ 439 $ 50 $ 1,260 Firm-fixed-price 283 256 253 792 Time-and-materials and fixed-price-level-of-effort 124 145 122 391 Total $ 1,178 $ 840 $ 425 $ 2,443 Disaggregated revenue by customer-type was as follows: Three Months Ended March 30, 2018 Defense Solutions Civil Health Total (in millions) DoD $ 1,032 $ 23 $ 92 $ 1,147 Other government agencies (1) 45 589 298 932 Commercial and non-U.S. customers 101 228 35 364 Total $ 1,178 $ 840 $ 425 $ 2,443 Disaggregated revenue by geographic location was as follows: Three Months Ended March 30, 2018 Defense Solutions Civil Health Total (in millions) United States $ 1,088 $ 696 $ 425 $ 2,209 International 90 144 — 234 Total $ 1,178 $ 840 $ 425 $ 2,443

Contract Asset and Liabilities

Contract Asset and Liabilities (Tables)	3 Months Ended
	Mar. 30, 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 March 30, December 30, 2017 (1) (in millions) Contract assets - current: Unbilled receivables (2) Receivables, net $ 836 $ 844 Transition costs and project assets Inventory, prepaid expenses and other current assets 114 59 $ 950 $ 903 Contract assets - non-current: Transition costs and project assets Other assets $ 14 $ 13 Contract liabilities - current: Deferred revenue Accounts payable and accrued liabilities $ 406 $ 293 Contract liabilities - non-current: Deferred revenue Other long-term liabilities $ 22 $ 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 (ASC 606) . (2) Balances exclude $459 million and $234 million determined to be billable at March 30, 2018, and December 30, 2017, respectively.

Acquisitions (Tables)

Acquisitions (Tables)	3 Months Ended
	Mar. 30, 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 March 30, March 31, (in millions) Acquisition costs $ — $ 1 Integration costs 11 18 Total acquisition and integration costs $ 11 $ 19

Restructuring Expenses (Tables)

Restructuring Expenses (Tables)	3 Months Ended
	Mar. 30, 2018
Restructuring and Related Activities [Abstract]
Schedule of restructuring expenses	The restructuring expenses related to this program were as follows: Three Months Ended March 30, March 31, (in millions) Severance costs $ 1 $ 10 Lease termination expenses 5 3 Restructuring expenses related to the IS&GS Business $ 6 $ 13
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 5 6 Cash payments (4 ) (4 ) (8 ) Balance as of March 30, 2018 $ 2 $ 5 $ 7

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 30, 2018
Fair Value Disclosures [Abstract]
Schedule of financial assets measured on a recurring basis	The Company's financial instruments measured on a recurring basis at fair value consisted of the following: March 30, 2018 December 29, 2017 Carrying value Fair value Carrying value Fair value (in millions) Financial assets: Derivatives $ 51 $ 51 $ 37 $ 37 Financial liabilities: Derivatives 7 7 — —

Goodwill (Tables)

Goodwill (Tables)	3 Months Ended
	Mar. 30, 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 (6 ) 8 — 2 Goodwill at March 30, 2018 $ 2,049 $ 2,006 $ 921 $ 4,976

Intangible Assets (Tables)

Intangible Assets (Tables)	3 Months Ended
	Mar. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of intangible assets	Intangible assets consisted of the following: March 30, 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 $ 1,013 $ (235 ) $ 778 $ 1,013 $ (187 ) $ 826 Software and technology 89 (66 ) 23 89 (64 ) 25 Customer relationships 4 (3 ) 1 4 (3 ) 1 Backlog — — — 158 (158 ) — Total finite-lived intangible assets 1,106 (304 ) 802 1,264 (412 ) 852 Indefinite-lived intangible assets: Trade names 4 — 4 4 — 4 Total intangible assets $ 1,110 $ (304 ) $ 806 $ 1,268 $ (412 ) $ 856
Schedule of estimated annual amortization expense	The estimated annual amortization expense as of March 30, 2018 , was as follows: Fiscal Year Ending (in millions) 2018 (remainder of year) $ 151 2019 173 2020 128 2021 106 2022 92 2023 and thereafter 152 $ 802

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	3 Months Ended
	Mar. 30, 2018
Property, Plant and Equipment [Abstract]
Schedule of Property, plant and equipment, net	Property, plant and equipment, net consisted of the following: March 30, December 29, (in millions) Computers and other equipment $ 196 $ 194 Leasehold improvements 172 171 Buildings and improvements 56 54 Office furniture and fixtures 34 34 Land 40 49 Construction in progress 55 44 553 546 Less: accumulated depreciation and amortization (326 ) (314 ) $ 227 $ 232

Derivative Instruments (Tables)

Derivative Instruments (Tables)	3 Months Ended
	Mar. 30, 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 March 30, December 29, (in millions) Cash flow interest rate swaps Other assets 51 37 Liability Derivatives Balance sheet line item March 30, December 29, (in millions) Fair value interest rate swaps Other long-term liabilities $ 6 $ — Cash flow interest rate swaps Other long-term liabilities 1 — $ 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 March 30, December 29, March 30, December 29, (in millions) Long-term debt, net of current portion $ 443 $ 449 $ (6 ) $ —
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 March 30, March 31, (in millions) Total interest expense, net presented in the condensed consolidated statements of income in which the effects of cash flow hedges are recorded $ 34 $ 36 Amount recognized in other comprehensive income 14 1 Amount reclassified from accumulated other comprehensive income to interest expense, net (1 ) 1

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 30, 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 March 30, 2018 (1) December 29, 2017 (1) (in millions) Senior secured notes: $450 million notes, due December 2020 4.45% 4.53% $ 443 $ 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 3.69% 4.18% 636 644 $310 million Term Loan A, due August 2022 3.69% 4.18% 267 270 $1,131 million Term Loan B, due August 2023 3.69% 4.07% 1,098 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 24 27 Total long-term debt 3,088 3,111 Less: current portion 81 55 Total long-term debt, net of current portion $ 3,007 $ 3,056

Accumulated Other Comprehensi43

Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 30, 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 income 3 14 — 17 Taxes 1 (3 ) — (2 ) Reclassification from accumulated other comprehensive income — (1 ) — (1 ) Balance at March 30, 2018 $ 24 $ 34 $ (2 ) $ 56

Earnings Per Share (EPS) (Table

Earnings Per Share (EPS) (Tables)	3 Months Ended
	Mar. 30, 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 March 30, March 31, (in millions) Basic weighted average number of shares outstanding 152 150 Dilutive common share equivalents—stock options and other stock awards 2 3 Diluted weighted average number of shares outstanding 154 153

Supplementary Cash Flow Infor45

Supplementary Cash Flow Information and Restricted Cash (Tables)	3 Months Ended
	Mar. 30, 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: Three Months Ended March 30, March 31, (in millions) Supplementary cash flow information: Cash paid for interest $ 32 $ 32 Cash paid for income taxes, net of refunds 2 1 Non-cash financing activity: Capital lease obligation — 6 Purchase of non-controlling interests 7 — 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: March 30, December 29, (in millions) Cash and cash equivalents $ 215 $ 390 Restricted cash 42 32 Total cash, cash equivalents and restricted cash $ 257 $ 422

Business Segments (Tables)

Business Segments (Tables)	3 Months Ended
	Mar. 30, 2018
Segment Reporting [Abstract]
Schedule of segment reporting information by segment	The segment information for the periods presented was as follows: Three Months Ended March 30, March 31, (in millions) Revenues: Defense Solutions $ 1,178 $ 1,294 Civil 840 842 Health 425 443 Corporate — 1 Total revenues $ 2,443 $ 2,580 Operating income (loss): Defense Solutions $ 85 $ 79 Civil 74 54 Health 42 47 Corporate (42 ) (39 ) Total operating income $ 159 $ 141

Nature of Operations and Basis

Nature of Operations and Basis of Presentation (Additional Information) (Detail) $ in Millions	3 Months Ended
	Mar. 30, 2018USD ($)segment	Mar. 31, 2017USD ($)	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	$ (165)	$ (154)
Decrease in other, operative activities	7	3
Increase in other, financing activities	$ 4	1
Cost of Revenue
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment		(37)
Selling, General and Administrative Expenses
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment		37
Accounting Standards Update 2016-18
Significant Accounting Policies [Line Items]
Net decrease in operating cash flows		16
Increase in cash, cash equivalents and restricted cash		16
Accounting Standards Update 2016-15
Significant Accounting Policies [Line Items]
Decrease in other, operative activities		1
Increase in other, 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	Mar. 30, 2018	Dec. 30, 2017	Dec. 29, 2017
ASSETS
Receivables, net	$ 1,914	$ 1,835	$ 1,831
Inventory, prepaid expenses and other current assets	506	450	453
Equity [Abstract]
Accumulated earnings (deficit)	37	(15)	(7)
Accumulated other comprehensive income	$ 56	42	$ 33
Adjustments due to ASU 2014-09
ASSETS
Receivables, net		4
Inventory, prepaid expenses and other current assets		(3)
Equity [Abstract]
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 [Abstract]
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 [Abstract]
Accumulated earnings (deficit)		(6)
Accumulated other comprehensive income		$ 6

Significant Accounting Polici49

Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017	Dec. 29, 2017
Significant Accounting Policies [Line Items]
Net favorable impact to income before income taxes	$ 35	$ 22
Impact on diluted EPS attributable to Leidos common stockholders (usd per share)	$ 0.17	$ 0.09
Revenue recognized for perfomance obligation satisfied in the previous periods	$ 34
Accounts payable and accrued liabilities	1,622		$ 1,639
Cash and Cash Equivalents
Significant Accounting Policies [Line Items]
Accounts payable and accrued liabilities	$ 124		$ 169

Revenue (Details)

Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017	Dec. 30, 2017	Dec. 29, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Receivables, net	$ 1,914		$ 1,835	$ 1,831
Inventory, prepaid expenses and other current assets	506		450	453
Accumulated earnings (deficit)	37		$ (15)	$ (7)
Revenues	2,443	$ 2,580
Cost of revenues	2,086	2,233
Operating income	159	$ 141
As Adjusted
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Receivables, net	1,909
Inventory, prepaid expenses and other current assets	509
Accumulated earnings (deficit)	35
Revenues	2,438
Cost of revenues	2,083
Operating income	$ 157

Revenue (Narrative) (Details)

Revenue (Narrative) (Details) $ in Billions	3 Months Ended
	Mar. 30, 2018USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-03-31
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligations, which are expected to be recognized as revenue	$ 5.3
Remaining performance obligations, which are expected to be recognized as revenue, ( in months/years)	9 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-12-29
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligations, which are expected to be recognized as revenue	$ 1.2
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, Initial Application Period Cumulative Effect Transition [Line Items]
Remaining performance obligations, which are expected to be recognized as revenue	$ 8.9
Remaining performance obligations, which are expected to be recognized as revenue, ( in months/years)

Revenue (Disaggregation of reve

Revenue (Disaggregation of revenue) (Details) $ in Millions	3 Months Ended
	Mar. 30, 2018USD ($)
Disaggregation of Revenue [Line Items]
Revenue	$ 2,443
United States
Disaggregation of Revenue [Line Items]
Revenue	2,209
International
Disaggregation of Revenue [Line Items]
Revenue	234
Cost-reimbursement and fixed-price-incentive- fee
Disaggregation of Revenue [Line Items]
Revenue	1,260
Firm-fixed-price
Disaggregation of Revenue [Line Items]
Revenue	792
Time-and-materials and fixed-price-level-of-effort
Disaggregation of Revenue [Line Items]
Revenue	391
DoD
Disaggregation of Revenue [Line Items]
Revenue	1,147
Other government agencies
Disaggregation of Revenue [Line Items]
Revenue	932
Commercial and non-U.S. customers
Disaggregation of Revenue [Line Items]
Revenue	364
Defense Solutions
Disaggregation of Revenue [Line Items]
Revenue	1,178
Defense Solutions | United States
Disaggregation of Revenue [Line Items]
Revenue	1,088
Defense Solutions | International
Disaggregation of Revenue [Line Items]
Revenue	90
Defense Solutions | Cost-reimbursement and fixed-price-incentive- fee
Disaggregation of Revenue [Line Items]
Revenue	771
Defense Solutions | Firm-fixed-price
Disaggregation of Revenue [Line Items]
Revenue	283
Defense Solutions | Time-and-materials and fixed-price-level-of-effort
Disaggregation of Revenue [Line Items]
Revenue	124
Defense Solutions | DoD
Disaggregation of Revenue [Line Items]
Revenue	1,032
Defense Solutions | Other government agencies
Disaggregation of Revenue [Line Items]
Revenue	45
Defense Solutions | Commercial and non-U.S. customers
Disaggregation of Revenue [Line Items]
Revenue	101
Civil
Disaggregation of Revenue [Line Items]
Revenue	840
Civil | United States
Disaggregation of Revenue [Line Items]
Revenue	696
Civil | International
Disaggregation of Revenue [Line Items]
Revenue	144
Civil | Cost-reimbursement and fixed-price-incentive- fee
Disaggregation of Revenue [Line Items]
Revenue	439
Civil | Firm-fixed-price
Disaggregation of Revenue [Line Items]
Revenue	256
Civil | Time-and-materials and fixed-price-level-of-effort
Disaggregation of Revenue [Line Items]
Revenue	145
Civil | DoD
Disaggregation of Revenue [Line Items]
Revenue	23
Civil | Other government agencies
Disaggregation of Revenue [Line Items]
Revenue	589
Civil | Commercial and non-U.S. customers
Disaggregation of Revenue [Line Items]
Revenue	228
Health
Disaggregation of Revenue [Line Items]
Revenue	425
Health | United States
Disaggregation of Revenue [Line Items]
Revenue	425
Health | International
Disaggregation of Revenue [Line Items]
Revenue	0
Health | Cost-reimbursement and fixed-price-incentive- fee
Disaggregation of Revenue [Line Items]
Revenue	50
Health | Firm-fixed-price
Disaggregation of Revenue [Line Items]
Revenue	253
Health | Time-and-materials and fixed-price-level-of-effort
Disaggregation of Revenue [Line Items]
Revenue	122
Health | DoD
Disaggregation of Revenue [Line Items]
Revenue	92
Health | Other government agencies
Disaggregation of Revenue [Line Items]
Revenue	298
Health | Commercial and non-U.S. customers
Disaggregation of Revenue [Line Items]
Revenue	$ 35

Contract Asset and Liabilitie53

Contract Asset and Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 30, 2018	Dec. 29, 2017
Schedule Of Contract Assets And Liabilities [Line Items]
Contract assets - current	$ 950	$ 903
Contract assets - non-current	14	13
Contract liabilities - current	406	293
Contract liabilities - non-current	22	17
Contract assets part of receivable	459	234
Contract liability revenue recognized	55
Amortization of transition and project cots	3
Receivables, net
Schedule Of Contract Assets And Liabilities [Line Items]
Contract assets - current	836	844
Inventory, prepaid expenses and other current assets
Schedule Of Contract Assets And Liabilities [Line Items]
Contract assets - current	$ 114	$ 59

Acquisitions (Textual) (Details

Acquisitions (Textual) (Details) - USD ($) $ in Millions	Jan. 18, 2018	Mar. 30, 2018	Mar. 31, 2017
Business Acquisition [Line Items]
Cash paid, operating activities		$ (22)	$ 71
Cash paid, investing activities		$ 96	$ 5
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) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017
Business Acquisition [Line Items]
Total acquisition and integration costs	$ 11	$ 19
Information Systems & Global Solutions Business of Lockheed Martin
Business Acquisition [Line Items]
Acquisition costs	0	1
Integration costs	11	18
Total acquisition and integration costs	$ 11	$ 19

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 ($)extension	Mar. 31, 2017USD ($)	Feb. 28, 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		12 Months Ended	21 Months Ended
	Mar. 30, 2018	Mar. 31, 2017	Dec. 29, 2017	Mar. 30, 2018
Restructuring Reserve [Roll Forward]
Restructuring expenses	$ 6	$ 13		$ 55
Restructuring Due To IS&GS Acquisition
Restructuring Reserve [Roll Forward]
Restructuring reserve, opening balance	9	8	$ 8
Restructuring expenses	6	13	37
Cash payments	(8)		(36)
Restructuring reserve, closing balance	$ 7		9	7
Period to settle restructuring liability, minimum (in years)	1 year
Restructuring Due To IS&GS Acquisition | Severance costs
Restructuring Reserve [Roll Forward]
Restructuring reserve, opening balance	$ 5	7	7
Restructuring expenses	1	10	18
Cash payments	(4)		(20)
Restructuring reserve, closing balance	2		5	2
Restructuring Due To IS&GS Acquisition | Lease Termination Expenses
Restructuring Reserve [Roll Forward]
Restructuring reserve, opening balance	4	1	1
Restructuring expenses	5	$ 3	19
Cash payments	(4)		(16)
Restructuring reserve, closing balance	$ 5		$ 4	$ 5

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($)	Mar. 30, 2018	Dec. 29, 2017
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
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
Stated interest rate (in percentage)	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%
Carrying value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative asset	$ 51,000,000	$ 37,000,000
Derivative liability	7,000,000	0
Fair value of notes receivable	63,000,000	63,000,000
Fair value of debt instrument	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	51,000,000	37,000,000
Derivative liability	7,000,000	0
Fair value of debt instrument	$ 3,200,000,000	$ 3,200,000,000

Goodwill (Schedule of Changes i

Goodwill (Schedule of Changes in Goodwill by Segment) (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 30, 2018	Mar. 31, 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	2,000,000		15,000,000
Ending balance, Goodwill	4,976,000,000		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	(6,000,000)		7,000,000
Ending balance, Goodwill	2,049,000,000		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	8,000,000		8,000,000
Ending balance, Goodwill	2,006,000,000		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
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	Mar. 30, 2018	Dec. 29, 2017
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying value	$ 1,106	$ 1,264
Accumulated amortization	(304)	(412)
Net carrying value	802	852
Total intangible assets, Gross carrying value	1,110	1,268
Total intangible assets, Net carrying value	806	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	1,013	1,013
Accumulated amortization	(235)	(187)
Net carrying value	778	826
Software and technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying value	89	89
Accumulated amortization	(66)	(64)
Net carrying value	23	25
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross carrying value	4	4
Accumulated amortization	(3)	(3)
Net carrying value	1	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
	Mar. 30, 2018	Mar. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 50	$ 69

Intangible Assets (Amortization

Intangible Assets (Amortization of Intangibles) (Details) - USD ($) $ in Millions	Mar. 30, 2018	Dec. 29, 2017
Estimated Annual Intangible Amortization Expense
2018 (remainder of year)	$ 151
2,019	173
2,020	128
2,021	106
2,022	92
2023 and thereafter	152
Net carrying value	$ 802	$ 852

Property, Plant and Equipment63

Property, Plant and Equipment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017	Dec. 29, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 553		$ 546
Less: accumulated depreciation and amortization	(326)		(314)
Property, plant and equipment, net	227		232
Depreciation	13	$ 13
Asset impairment charges	7	$ 0
Computers and other equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	196		194
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	172		171
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	56		54
Office furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	34		34
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	40		49
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	55		$ 44
Corporate
Property, Plant and Equipment [Line Items]
Asset impairment charges	$ 7

Derivative Instruments (Details

Derivative Instruments (Details) - USD ($)	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017	Feb. 28, 2018	Dec. 29, 2017
Derivative [Line Items]
Carrying amount of hedged item	$ 443,000,000			$ 449,000,000
Cumulative amount of fair value adjustment included within the hedged item	(6,000,000)			0
Total interest expense, net presented in the condensed consolidated statements of income in which the effects of cash flow hedges are recorded	34,000,000	$ 36,000,000
Cash flow hedges, amount recognized in other comprehensive income	14,000,000	1,000,000
Gains expected to be reclassified in the next 12 months	11,000,000
Designated as Hedging Instrument
Derivative [Line Items]
Liability Derivatives	7,000,000			0
Asset Derivatives | Designated as Hedging Instrument | $450 million notes, due December 2020
Derivative [Line Items]
Hedged instrument, face amount	$ 450,000,000
Stated interest rate (in percentage)	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
Stated interest rate (in percentage)	4.45%
Fair Value Hedging | Asset Derivatives | Other long-term liabilities | Designated as Hedging Instrument
Derivative [Line Items]
Liability Derivatives	$ 6,000,000			0
Cash Flow Hedging | Asset Derivatives | Other assets | Designated as Hedging Instrument
Derivative [Line Items]
Asset Derivatives	51,000,000			37,000,000
Cash Flow Hedging | Asset Derivatives | Other long-term liabilities | Designated as Hedging Instrument
Derivative [Line Items]
Liability Derivatives	1,000,000			$ 0
Secured Debt | Designated as Hedging Instrument
Derivative [Line Items]
Hedged instrument, face amount	1,600,000,000
Secured Debt | Interest Rate Swap, Maturity Date August Twenty Twenty Two [Member] | 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 Twenty Twenty Two [Member] | Designated as Hedging Instrument | Variable Rate Loan
Derivative [Line Items]
Hedged instrument, face amount			$ 250,000,000
Stated interest rate (in percentage)			2.59%
Secured Debt | Interest Rate Swap, Maturity Date December Twenty Twenty One [Member] | Designated as Hedging Instrument
Derivative [Line Items]
Hedged instrument, face amount			$ 1,100,000,000
Stated interest rate (in percentage)			1.08%
Interest Expense [Member]
Derivative [Line Items]
Cash flow hedges, amount reclassified from accumulated other comprehensive income to interest expense, net	$ (1,000,000)	$ 1,000,000

Debt (Summary of debt) (Detail)

Debt (Summary of debt) (Detail) - USD ($)	Mar. 30, 2018	Dec. 29, 2017
Debt Instrument [Line Items]
Total long-term debt	$ 3,088,000,000	$ 3,111,000,000
Less: current portion	81,000,000	55,000,000
Total long-term debt, net of current portion	3,007,000,000	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	$ 24,000,000	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	$ 443,000,000	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	$ 636,000,000	644,000,000
Stated interest rate (in percentage)	3.69%
Effective interest rate	4.18%
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	$ 267,000,000	270,000,000
Stated interest rate (in percentage)	3.69%
Effective interest rate	4.18%
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	$ 1,098,000,000	1,101,000,000
Stated interest rate (in percentage)	3.69%
Effective interest rate	4.07%
Senior unsecured notes, face amount	$ 1,131,000,000
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 ($)	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017	Dec. 29, 2017
Debt Instrument [Line Items]
Long-term debt	$ 3,114,000,000		$ 3,129,000,000
Unamortized debt discounts and deferred debt issuances costs	44,000,000		$ 45,000,000
Repayments of debt	15,000,000	$ 20,000,000
Secured Debt | $1,131 million Term Loan B, due August 2023
Debt Instrument [Line Items]
Note payable, face amount	$ 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%
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	$ 6,000,000

Debt (Revolving Credit Facility

Debt (Revolving Credit Facility) (Detail)	Mar. 30, 2018USD ($)
Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Unsecured borrowing capacity	$ 750,000,000

Accumulated Other Comprehensi68

Accumulated Other Comprehensive Income (Schedule of Accumulated Other Comprehensive Loss) (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 30, 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
Adjusted balance		3,384
Ending balance	3,431	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	$ 9
Adjusted balance		42	42
Other comprehensive income	17	55
Taxes	(2)	(18)
Reclassification from accumulated other comprehensive income (loss)	(1)
Ending balance	56	33
Foreign currency translation adjustments
AOCI, Net of Tax [Roll Forward]
Beginning balance	17	(7)
Cumulative adjustments related to ASU adoptions (Note 2)			3
Adjusted balance			20
Other comprehensive income	3	36
Taxes	1	(12)
Reclassification from accumulated other comprehensive income (loss)	0
Ending balance	24	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
Adjusted balance			24
Other comprehensive income	14	10
Taxes	(3)	(6)
Reclassification from accumulated other comprehensive income (loss)	(1)
Ending balance	34	14
Pension adjustments
AOCI, Net of Tax [Roll Forward]
Beginning balance	2	(7)
Cumulative adjustments related to ASU adoptions (Note 2)			(4)
Adjusted balance			$ (2)
Other comprehensive income	0	9
Taxes	0	0
Reclassification from accumulated other comprehensive income (loss)	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
	Mar. 30, 2018	Mar. 31, 2017
Earnings Per Share [Abstract]
Basic weighted average number of shares outstanding (shares)	152	150
Dilutive common share equivalents-stock options and other stock awards (shares)	2	3
Diluted weighted average number of shares outstanding (shares)	154	153

Earnings Per Share (EPS) (Narra

Earnings Per Share (EPS) (Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 30, 2018USD ($)
Earnings Per Share [Abstract]
Payments for repurchase of common stock	$ 10

Supplementary Cash Flow Infor71

Supplementary Cash Flow Information and Restricted Cash (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017	Dec. 29, 2017	Dec. 30, 2016
Supplementary cash flow information:
Cash paid for interest	$ 32	$ 32
Cash paid for income taxes, net of refunds	2	1
Noncash Investing and Financing Items [Abstract]
Capital lease obligation	0	6
Purchase of non-controlling interests	7	0
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents
Cash and cash equivalents	390
Restricted cash	42		$ 32
Total cash, cash equivalents and restricted cash	$ 257	$ 242	$ 422	$ 396

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate	18.40%	31.50%

Business Segments (Schedule of

Business Segments (Schedule of Segment Reporting Information by Segment) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 30, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Revenues	$ 2,443	$ 2,580
Operating income (loss)	159	141
Operating Segments | Defense Solutions
Segment Reporting Information [Line Items]
Revenues	1,178	1,294
Operating income (loss)	85	79
Operating Segments | Civil
Segment Reporting Information [Line Items]
Revenues	840	842
Operating income (loss)	74	54
Operating Segments | Health
Segment Reporting Information [Line Items]
Revenues	425	443
Operating income (loss)	42	47
Corporate
Segment Reporting Information [Line Items]
Revenues	0	1
Operating income (loss)	$ (42)	$ (39)

Contingencies (Additional Infor

Contingencies (Additional Information) (Detail) € in Millions, $ in Millions	Apr. 10, 2018USD ($)	Sep. 29, 2017USD ($)	Mar. 30, 2018USD ($)	Apr. 30, 2012LegalMatter	Jan. 31, 2017USD ($)	Nov. 10, 2015USD ($)	Dec. 31, 2013USD ($)	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					$ 63		$ 48	€ 39
MSA Venture
Legal Proceedings [Line Items]
Estimate of possible loss			$ 64			$ 64
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		$ 439
Information Systems & Global Solutions Business of Lockheed Martin | MSA Venture
Legal Proceedings [Line Items]
Indemnification asset			$ 1
Subsequent Event | Virnet X Inc
Legal Proceedings [Line Items]
Amount awarded to other party	$ 502

Commitments (Additional Informa

Commitments (Additional Information) (Detail) - USD ($) $ in Millions	Jan. 24, 2018	Mar. 30, 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		$ 137
Standby Letters of Credit and Surety Bonds
Other Commitments And Contingencies [Line Items]
Debt instrument term		4 years

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 30, 2018	Mar. 30, 2018	Mar. 31, 2017
Subsequent Event [Line Items]
Repayments of debt		$ 15	$ 20
Secured Debt | Subsequent Event
Subsequent Event [Line Items]
Repayments of debt	$ 10