L3 10-Q 27 Apr 17 2017 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2017	Apr. 21, 2017
Document And Entity Information [Abstract]
Entity Registrant Name	L3 TECHNOLOGIES, INC.
Entity Central Index Key	1,039,101
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		77,877,337
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2017

UNAUDITED CONDENSED CONSOLIDATE

UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 230	$ 363
Billed receivables, net of allowances of $13 in 2017 and 2016	802	731
Contracts in process	2,254	2,055
Inventories	353	330
Other current assets	233	218
Total current assets	3,872	3,697
Property, plant and equipment, net	1,123	1,121
Goodwill	6,679	6,560
Identifiable intangible assets	242	238
Other assets	248	249
Total assets	12,164	11,865
Current liabilities:
Accounts payable, trade	427	299
Accrued employment costs	449	516
Accrued expenses	390	375
Advance payments and billings in excess of costs incurred	489	492
Income taxes payable	30	22
Other current liabilities	444	431
Total current liabilities	2,229	2,135
Pension and postretirement benefits	1,184	1,177
Deferred income taxes	258	236
Other liabilities	365	368
Long-term debt	3,326	3,325
Total liabilities	7,362	7,241
Commitments and contingencies (see Note 18)
Shareholders' equity:
Common stock: $.01 par value; 300,000,000 shares authorized, 77,895,733 shares outstanding at March 31, 2017 and 77,232,204 shares outstanding at December 31, 2016	6,330	6,285
Treasury stock (at cost), 82,385,075 shares at March 31, 2017 and December 31, 2016	(7,224)	(7,224)
Retained earnings	6,323	6,218
Accumulated other comprehensive loss	(698)	(726)
Total shareholders' equity	4,731	4,553
Noncontrolling interests	71	71
Total equity	4,802	4,624
Total liabilities and equity	$ 12,164	$ 11,865

UNAUDITED CONDENSED CONSOLIDAT3

UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Allowances for billed receivables	$ 13	$ 13
Shareholders' equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares outstanding (in shares)	77,895,733	77,232,204
Treasury stock at cost (in shares)	82,385,075	82,385,075

UNAUDITED CONDENSED CONSOLIDAT4

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Net sales:
Products	$ 1,600	$ 1,423
Services	1,069	930
Total net sales	2,669	2,353
Cost of sales:
Products	(1,426)	(1,266)
Services	(990)	(835)
Total cost of sales	(2,416)	(2,101)
Operating income	253	252
Interest expense	(42)	(41)
Interest and other income, net	5	4
Income from continuing operations before income taxes	216	215
Provision for income taxes	(48)	(48)
Income from continuing operations	168	167
Income from discontinued operations, net of income taxes	0	63
Net income	168	230
Net income from continuing operations attributable to noncontrolling interests	(4)	(3)
Net income attributable to L3	$ 164	$ 227
Basic earnings per share attributable to common shareholders:
Continuing operations (in dollars per share)	$ 2.11	$ 2.11
Discontinued operations (in dollars per share)	0	0.81
Basic earnings per share (in dollars per share)	2.11	2.92
Diluted earnings per share attributable to common shareholders:
Continuing operations (in dollars per share)	2.07	2.08
Discontinued operations (in dollars per share)	0	0.79
Diluted earnings per share (in dollars per share)	2.07	2.87
Cash dividends declared per common share (in dollars per share)	$ 0.75	$ 0.70
Weighted average common shares outstanding:
Basic (in shares)	77.7	77.8
Diluted (in shares)	79.3	79

UNAUDITED CONDENSED CONSOLIDAT5

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 25, 2016
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income		$ 168	$ 230
Other comprehensive income:
Foreign currency translation adjustments		19	1
Unrealized gains on hedging instruments	[1]	0	7
Pension and postretirement benefit plans:
Amortization of net loss and prior service cost previously recognized	[2]	9	8
Total other comprehensive income		28	16
Comprehensive income		196	246
Comprehensive income attributable to noncontrolling interests		(4)	(3)
Comprehensive income attributable to L3		$ 192	$ 243
[1]	Net of income taxes of $3 million for the quarterly period ended March 25, 2016.
[2]	Net of income taxes of $6 million and $4 million for the quarterly periods ended March 31, 2017 and March 25, 2016, respectively.

UNAUDITED CONDENSED CONSOLIDAT6

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Income tax expense (benefit) on unrealized gainson hedging instruments		$ 3
Income tax (expense) on amortization of net loss and prior service cost previously recognized	$ 6	$ 4

UNAUDITED CONDENSED CONSOLIDAT7

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Millions	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Noncontrolling Interests [Member]	Total
Beginning Balance at Dec. 31, 2015	$ 1	$ 6,051	$ (6,851)	$ 5,728	$ (574)	$ 74	$ 4,429
Beginning Balance (in shares) at Dec. 31, 2015	78,100,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income				227		3	230
Other comprehensive income					16		16
Distributions to noncontrolling interests						(4)	(4)
Cash dividends declared				(54)			(54)
Shares issued:
Employee savings plans		32					32
Employee savings plans (in shares)	300,000
Exercise of stock options		14					14
Exercise of stock options (in shares)	200,000
Employee stock purchase plan		0					0
Employee stock purchase plan (in shares)	100,000
Vesting of restricted stock and performance units							0
Vesting of restricted stock and performance units (in shares)	500,000
Repurchases of common stock to satisfy tax withholding obligations		(20)					(20)
Repurchases of common stock to satisfy tax withholding obligations (in shares)	(200,000)
Stock-based compensation expense		6					6
Treasury stock purchased			(198)				(198)
Treasury stock purchased (in shares)	(1,700,000)
Ending Balance at Mar. 25, 2016	$ 1	6,083	(7,049)	5,901	(558)	73	4,451
Ending Balance (in shares) at Mar. 25, 2016	77,300,000
Beginning Balance at Dec. 31, 2016	$ 1	6,284	(7,224)	6,218	(726)	71	4,624
Beginning Balance (in shares) at Dec. 31, 2016	77,200,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income				164		4	168
Other comprehensive income					28		28
Distributions to noncontrolling interests						(4)	(4)
Cash dividends declared				(59)			(59)
Shares issued:
Employee savings plans		36					36
Employee savings plans (in shares)	200,000
Exercise of stock options		13					13
Exercise of stock options (in shares)	200,000
Employee stock purchase plan		0					0
Employee stock purchase plan (in shares)	100,000
Vesting of restricted stock and performance units							0
Vesting of restricted stock and performance units (in shares)	300,000
Repurchases of common stock to satisfy tax withholding obligations		(18)					(18)
Repurchases of common stock to satisfy tax withholding obligations (in shares)	(100,000)
Stock-based compensation expense		14					$ 14
Treasury stock purchased (in shares)							0
Ending Balance at Mar. 31, 2017	$ 1	$ 6,329	$ (7,224)	$ 6,323	$ (698)	$ 71	$ 4,802
Ending Balance (in shares) at Mar. 31, 2017	77,900,000

UNAUDITED CONDENSED CONSOLIDAT8

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical) - $ / shares	Feb. 13, 2017	Mar. 31, 2017	Mar. 25, 2016
UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF EQUITY [Abstract]
Cash dividends declared per share (in dollars per share)	$ 0.75	$ 0.75	$ 0.70

UNAUDITED CONDENSED CONSOLIDAT9

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Operating activities:
Net income	$ 168	$ 230
Less: Income from discontinued operations, net of tax	0	(63)
Income from continuing operations	168	167
Depreciation of property, plant and equipment	41	40
Amortization of intangibles and other assets	13	10
Deferred income tax provision	17	12
Stock-based employee compensation expense	14	6
Contributions to employee savings plans in L3's common stock	36	30
Amortization of pension and postretirement benefit plans net loss and prior service cost	15	12
Amortization of bond discounts and deferred debt issue costs (included in interest expense)	1	2
Other non-cash items	4	1
Changes in operating assets and liabilities, excluding amounts from acquisitions and divestitures, and discontinued operations:
Billed receivables	(67)	(32)
Contracts in process	(205)	(148)
Inventories	(11)	(19)
Other assets	1	4
Accounts payable, trade	124	115
Accrued employment costs	(76)	(46)
Accrued expenses	21	16
Advance payments and billings in excess of costs incurred	(7)	(64)
Income taxes	15	20
Other current liabilities	(3)	(6)
Pension and postretirement benefits	7	(1)
All other operating activities	(23)	(7)
Net cash from operating activities from continuing operations	85	112
Investing activities:
Business acquisitions, net of cash acquired	(139)	(27)
Proceeds from the sale of businesses, net of closing date cash balances	16	576
Capital expenditures	(42)	(35)
Dispositions of property, plant and equipment	1	7
Other investing activities	5	9
Net cash (used in) from investing activities from continuing operations	(159)	530
Financing activities:
Borrowings under revolving credit facility	664	217
Repayments of borrowings under revolving credit facility	(664)	(217)
Common stock repurchased	0	(198)
Dividends paid on L3's common stock	(61)	(58)
Proceeds from exercises of stock options	12	14
Proceeds from employee stock purchase plan	8	8
Repurchases of common stock to satisfy tax withholding obligations	(18)	(20)
Other financing activities	(4)	(5)
Net cash used in financing activities from continuing operations	(63)	(259)
Effect of foreign currency exchange rate changes on cash and cash equivalents	4	0
Net cash used in operating activities from discontinued operations	0	(56)
Net (decrease) increase in cash and cash equivalents	(133)	327
Cash and cash equivalents, beginning of the period	363	207
Cash and cash equivalents, end of the period	$ 230	$ 534

Description of Business

Description of Business	3 Months Ended
	Mar. 31, 2017
Description of Business [Abstract]
Description of Business	1. Description of Business L3 Technologies, Inc. (L3 Technologies Inc. and, together with its subsidiaries, referred to herein as L3 or the Company) is a prime contractor in Intelligence, Surveillance and Reconnaissance (ISR) systems, aircraft sustainment (including modifications, logistics and maintenance), simulation and training, night vision and image intensification equipment and security and detection systems. L3 is also a leading provider of a broad range of communication and electronic systems and products used on military and commercial platforms. The Company’s customers include the United States (U.S.) Department of Defense (DoD) and its prime contractors, U.S. Government intelligence agencies, the U.S. Department of Homeland Security (DHS), foreign governments, and domestic and international commercial customers. At December 31, 2016, the Company had the following three reportable segments: (1) Electronic Systems, (2) Aerospace Systems and (3) Communication Systems. Effective March 1, 2017, the Company realigned its Electronic Systems segment, which was separated into two segments named: (1) Electronic Systems and (2) Sensor Systems. Accordingly, the Company’s current structure consists of the following four segments: (1) Electronic Systems, (2) Aerospace Systems, (3) Communication Systems and (4) Sensor Systems. Electronic Systems provides a broad range of products and services for military and commercial customers in several niche markets across several business areas. The business areas are: Precision Engagement and Training, Power & Propulsion Systems, Aviation Products, Security & Detection Systems and Link U.S. operations. Aerospace Systems delivers integrated solutions for the global ISR market and provides engineering, modernization, upgrade, sustainment, and maintenance and logistics support for a wide variety of aircraft and ground systems. Aerospace Systems sells these products and services primarily to the DoD and select foreign governments. The business areas are: ISR Systems, Aircraft Systems and Vertex Aerospace. Communication Systems delivers products and services for the global communications market, specializing in strategic and tactical space, airborne, ground and sea-based communication systems. Communication Systems sells these products and services primarily to the DoD and select foreign governments. The business areas are: Broadband Communication Systems, Advanced Communications and Space & Power Systems. Sensor Systems provides diverse sensor technologies for the land, sea, air, space and cyber domains to military and commercial customers. The business areas are: Integrated Sensor Systems, Warrior Systems, Ocean Systems and Advanced Programs. The Company reports its segment results for all periods presented under the realigned business segments for the prior year to be consistent with the current presentation. On December 7, 2015, the Company entered into a definitive agreement to sell its National Security Solutions (NSS) business to CACI International Inc. The transaction was completed on February 1, 2016. NSS provided cybersecurity solutions, high-performance computing, enterprise IT services, analytics and intelligence analysis to the DoD, U.S. Government intelligence agencies, federal civilian agencies and foreign governments. In accordance with Accounting Standards Update (ASU) 2014-08, Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity Financial information with respect to the Company’s segments is included in Note 22 to the unaudited condensed consolidated financial statements and in Note 21 to the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016.

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2017
Basis of Presentation [Abstract]
Basis of Presentation	2. Basis of Presentation These unaudited condensed consolidated financial statements for the quarterly period ended March 31, 2017 should be read in conjunction with the audited consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016. Principles of Consolidation and Reporting The accompanying financial statements comprise the consolidated financial statements of L3. The consolidated financial statements of the Company include all wholly-owned and majority-owned subsidiaries. All significant intercompany transactions are eliminated in consolidation. Investments in equity securities, joint ventures and limited liability corporations over which the Company has significant influence but does not have voting control are accounted for using the equity method. Investments over which the Company does not have significant influence are accounted for using the cost method. For the classification of contract related assets and liabilities, the Company uses the duration of the related contract or program as its operating cycle, which may be longer than one year, and classifies them as current. Certain reclassifications have been made to conform prior-year amounts to the current-year presentation. The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X of the Securities and Exchange Commission (SEC). Accordingly, they do not include all of the disclosures required by U.S. GAAP for a complete set of annual audited financial statements. The December 31, 2016 condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by U.S. GAAP. In the opinion of management, all adjustments (consisting of normal and recurring adjustments) considered necessary for a fair statement of the results for the interim periods presented have been included. The results of operations for the interim periods are not necessarily indicative of results for the full year. It is generally the Company’s established practice to close its books for the quarters ending March, June and September on the Friday preceding the end of the calendar quarter. The interim unaudited condensed consolidated financial statements included herein have been prepared and are labeled based on that convention. The Company closes its books for annual periods on December 31 regardless of what day it falls on. Accounting Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of sales and costs of sales during the reporting period. The most significant of these estimates and assumptions for L3 relate to contract revenue, profit and loss recognition, fair values of assets acquired and liabilities assumed in business combinations, market values for inventories reported at lower of cost or market, pension and post-retirement benefit obligations, stock-based employee compensation expense, income taxes, including the valuations of deferred tax assets, litigation reserves and environmental obligations, accrued product warranty costs, useful lives and valuation of recorded amounts of long-lived assets, identifiable intangible assets and goodwill. Changes in estimates are reflected in the periods during which they become known. Actual amounts may differ from these estimates and could differ materially. Revisions or adjustments to estimates for a contract’s revenue, estimated costs at completion and estimated profit or loss are often required as work progresses under a contract, as experience is gained, as facts and circumstances change and as new information is obtained, even though the scope of work required under the contract may not change. Revisions or adjustments may also be required if contract modifications occur. The impact of revisions in profit (loss) estimates for all types of contracts subject to percentage-of-completion (POC) accounting are recognized on a cumulative catch-up basis in the period in which the revisions are made. The revisions in contract estimates, if significant, can materially affect the Company’s results of operations and cash flows, as well as reduce the valuations of receivables and inventories, and in some cases result in liabilities to complete contracts in a loss position. Aggregate net changes in contract estimates amounted to increases of $41 million, or 16%, of operating income ($0.33 per diluted share) for the quarterly period ended March 31, 2017, and increases of $56 million, or 22%, of operating income ($0.46 per diluted share) for the quarterly period ended March 25, 2016. Revenue Recognition Substantially all of the Company’s sales are generated from written contractual (revenue) arrangements. The sales price for the Company’s revenue arrangements are either fixed-price, cost-plus or time-and-material type. Depending on the contractual scope of work, the Company utilizes either contract accounting standards or accounting standards for revenue arrangements with commercial customers to account for these contracts. Approximately 50% of the Company’s net sales in 2016 were accounted for under contract accounting standards, of which approximately 41% were fixed-price type contracts and approximately 9% were cost-plus type contracts. For contracts that are accounted for under contract accounting standards, sales and profits are recognized based on: (1) a POC method of accounting (fixed-price type contracts), (2) allowable costs incurred plus the estimated profit on those costs (cost-plus type contracts), or (3) direct labor hours expended multiplied by the contractual fixed rate per hour plus incurred costs for material (time-and-material type contracts). Sales and profits on fixed-price type contracts that are covered by contract accounting standards are substantially recognized using POC methods of accounting. Sales and profits on fixed-price production contracts under which units are produced and delivered in a continuous or sequential process are recorded as units are delivered based on their contractual selling prices (the “units-of-delivery” method). Sales and profits on each fixed-price production contract under which units are not produced and delivered in a continuous or sequential process, or under which a relatively few number of units are produced, are recorded based on the ratio of actual cumulative costs incurred to the total estimated costs at completion of the contract, multiplied by the total estimated contract revenue, less cumulative sales recognized in prior periods (the “cost-to-cost” method). Under both POC methods of accounting, a single estimated total profit margin is used to recognize profit for each contract over its entire period of performance, which can exceed one year. Losses on contracts are recognized in the period in which they become evident. Amounts representing contract change orders or claims are included in sales only when they can be reliably estimated and their realization is reasonably assured. The impact of revisions of contract estimates, which may result from contract modifications, performance or other reasons, are recognized on a cumulative catch-up basis in the period in which the revisions are made. Sales and profits on cost-plus type contracts that are covered by contract accounting standards are recognized as allowable costs are incurred on the contract, at an amount equal to the allowable costs plus the estimated profit on those costs. The estimated profit on a cost-plus type contract is fixed or variable based on the contractual fee arrangement types. Incentive and award fees are the primary variable fee contractual arrangement types for the Company. Incentive and award fees on cost-plus type contracts are included as an element of total estimated contract revenues and are recorded as sales when a basis exists for the reasonable prediction of performance in relation to established contractual targets and the Company is able to make reasonably dependable estimates for them. Sales and profits on time-and-material type contracts are recognized on the basis of direct labor hours expended multiplied by the contractual fixed rate per hour, plus the actual costs of materials and other direct non-labor costs. Sales on arrangements for (1) fixed-price type contracts that require the Company to perform services that are not related to the production of tangible assets (Fixed-Price Service Contracts) and (2) certain commercial customers are recognized in accordance with accounting standards for revenue arrangements with commercial customers. Sales for the Company’s businesses whose customers are primarily commercial business enterprises are substantially all generated from single element revenue arrangements. Sales are recognized when there is persuasive evidence of an arrangement, delivery has occurred or services have been performed, the selling price to the buyer is fixed or determinable and collectability is reasonably assured. Sales for Fixed-Price Service Contracts that do not contain measurable units of work performed are generally recognized on a straight-line basis over the contractual service period, unless evidence suggests that the revenue is earned, or obligations fulfilled, in a different manner. Sales for Fixed-Price Service Contracts that contain measurable units of work performed are generally recognized when the units of work are completed. Sales and profit on cost-plus and time-and-material type contracts within the scope of accounting standards for revenue arrangements with commercial customers are recognized in the same manner as those within the scope of contract accounting standards, except for incentive and award fees. Cost-based incentive fees are recognized when they are realizable in the amount that would be due under the contractual termination provisions as if the contract was terminated. Performance based incentive fees and award fees are recorded as sales when objective evidence exists that the fees have been earned. For a more complete discussion of these estimates and assumptions, see the Annual Report on Form 10-K for the year ended December 31, 2016.

New Accounting Standards Implem

New Accounting Standards Implemented	3 Months Ended
	Mar. 31, 2017
New Accounting Standards Implemented [Abstract]
New Accounting Standards Implemented	3. New Accounting Standards Implemented In January 2017, the Financial Accounting Standards Board (FASB) issued ASU 2017-04, Simplifying the Test for Goodwill Impairment

Accounting Standards Issued and

Accounting Standards Issued and Not Yet Implemented	3 Months Ended
	Mar. 31, 2017
Accounting Standards Issued and Not Yet Implemented [Abstract]
Accounting Standards Issued and Not Yet Implemented	4. Accounting Standards Issued and Not Yet Implemented In March 2017, the FASB issued ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost In January 2017, the FASB issued ASU 2017-01, Clarifying the Definition of a Business In February 2016, the FASB issued ASU 2016-02, Leases In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers The Company will adopt the standard as of January 1, 2018, using the modified retrospective transition method and is currently evaluating the expected impact of the adoption on its consolidated financial statements, and related disclosures. Under the modified retrospective transition method, the Company will be required to calculate and record the cumulative effect of adopting the new standard as of January 1, 2018, in the Company’s Quarterly Report on Form 10-Q for the first quarter of 2018. The Company expects to estimate the cumulative effect of adopting the new standard as of January 1, 2018 in the second half of 2017 based on expected contracts in process at December 31, 2017. The Company has made progress toward completing its evaluation of the potential changes from adopting this new standard on its financial reporting and disclosures. Specifically, the Company has evaluated the impact of the standard on its various revenue streams. Based on progress made to date, the Company expects to recognize revenue over time on most of its contracts that are covered by current contract accounting standards by using cost inputs to measure progress toward the completion of its performance obligations, which is similar to the POC cost-to-cost method currently used on the majority of these contracts. Accordingly, the Company expects the adoption of this standard to primarily impact certain contracts currently covered by contract accounting standards that recognize revenue using the POC units-of-delivery method. Approximately 20% of the Company’s net sales used the POC units-of-delivery method to recognize revenue in 2016. Upon adoption, the Company expects to recognize revenue earlier in the performance period as costs are incurred, as opposed to when units are delivered, on some of these contracts that currently use the POC units-of-delivery method to recognize revenue. Additionally, the Company has also made progress on drafting its accounting policies affected by this standard, the redesign of internal controls over financial reporting related to the standard, as well as evaluating the expanded disclosure requirements. The Company expects to complete the evaluation of the impact of the accounting and disclosure changes on its business processes, controls and systems during the first half of 2017, and implement any changes to such business processes, controls and systems over the remainder of 2017. Other accounting standard updates effective for interim and annual periods beginning after December 31, 2017 are not expected to have an impact on the Company’s financial position, results of operations or cash flows.

Acquisitions and Divestitures

Acquisitions and Divestitures	3 Months Ended
	Mar. 31, 2017
Acquisitions and Divestitures [Abstract]
Acquisitions and Divestitures	5. Acquisitions and Divestitures Business Acquisitions The business acquisitions discussed below are included in the Company’s results of operations from their respective dates of acquisition. 2017 Business Acquisitions OceanServer Technology, Inc. (OceanServer) Explosive Trace Detection business of Implant Sciences Net sales and income before income taxes for OceanServer and the ETD business, included in L3’s unaudited condensed consolidated statement of operations for the quarterly period ended March 31, 2017, are presented in the table below. First Quarter Ended March 31, 2017 (in millions) Net sales $ 19 Income before income taxes $ 1 2016 Business Acquisitions MacDonald Humfrey (Automation) Limited Micreo Limited and Aerosim Advanced Technical Materials, Inc. (ATM) Acquisition Business Divestitures 2017 Business Divestitures CTC Aviation Jet Services Limited Divestiture. L3 Coleman Aerospace Divestiture. Display Product Line Divestiture. Discontinued Operations As discussed in Note 1, on February 1, 2016, the Company completed the sale of its NSS business to CACI International Inc. for a sales price of $547 million. The sales price was finalized as of September 23, 2016, with no significant changes to preliminary amounts. The table below presents the statement of operations data for NSS, which was previously a reportable segment and has been classified as a discontinued operation and includes allocated interest expense for debt not directly attributable or related to L3’s other operations. Interest expense was allocated in accordance with the accounting standards for discontinued operations and was based on the ratio of NSS’s net assets to the sum of: (1) total L3 consolidated net assets and (2) L3 consolidated total debt. First Quarter Ended March 25, 2016 (in millions) Net sales $ 86 Cost of sales (92 ) Gain related to business divestiture 64 Operating income from discontinued operations 58 Interest expense allocated to discontinued operations — Income from discontinued operations before income taxes 58 Income tax benefit 5 Income from discontinued operations, net of income taxes $ 63 Unaudited Pro Forma Statements of Operations Data The following unaudited pro forma Statements of Operations data present the combined results of the Company and its business acquisitions completed during the quarterly period ended March 31, 2017 and the year ended December 31, 2016, assuming that the business acquisitions completed during 2017 and 2016 had occurred on January 1, 2016 and January 1, 2015, respectively. The unaudited pro forma Statements of Operations data below include adjustments for additional amortization expense related to acquired intangible assets, depreciation and estimated reduction to interest income assuming the 2017 and 2016 acquisitions had occurred on January 1, 2016 and January 1, 2015, respectively. First Quarter Ended March 31, 2017 March 25, 2016 (in millions, except per share data) Pro forma net sales $ 2,672 $ 2,400 Pro forma income from continuing operations attributable to L3 $ 164 $ 165 Pro forma net income attributable to L3 $ 164 $ 228 Pro forma diluted earnings per share from continuing operations $ 2.07 $ 2.10 Pro forma diluted earnings per share $ 2.07 $ 2.89 The unaudited pro forma results disclosed in the table above are based on various assumptions and are not necessarily indicative of the results of operations that would have occurred had the Company completed these acquisitions on the dates indicated above.

Contracts in Process

Contracts in Process	3 Months Ended
	Mar. 31, 2017
Contracts in Process [Abstract]
Contracts in Process	6. Contracts in Process The components of contracts in process are presented in the table below. March 31, 2017 December 31, 2016 (in millions) Unbilled contract receivables, gross $ 2,116 $ 2,020 Unliquidated progress payments (807 ) (827 ) Unbilled contract receivables, net 1,309 1,193 Inventoried contract costs, gross 1,113 1,065 Unliquidated progress payments (168 ) (203 ) Inventoried contract costs, net 945 862 Total contracts in process $ 2,254 $ 2,055 Inventoried Contract Costs. The table below presents a summary of G&A, IRAD and B&P costs included in inventoried contract costs and the changes to them, including amounts charged to cost of sales by the Company’s U.S. Government contractor businesses for the periods presented. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Amounts included in inventoried contract costs at beginning of the period $ 173 $ 137 Contract costs incurred: IRAD and B&P 78 65 Other G&A 222 194 Total 300 259 Amounts charged to cost of sales (295 ) (239 ) Amounts included in inventoried contract costs at end of the period $ 178 $ 157 The table below presents a summary of selling, general and administrative expenses and research and development expenses for the Company’s commercial businesses, which are expensed as incurred and included in cost of sales on the unaudited condensed consolidated statements of operations. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Selling, general and administrative expenses $ 71 $ 52 Research and development expenses 15 11 Total $ 86 $ 63

Inventories

Inventories	3 Months Ended
	Mar. 31, 2017
Inventories [Abstract]
Inventories	7. Inventories Inventories at Lower of Cost or Realizable Value. March 31, 2017 December 31, 2016 (in millions) Raw materials, components and sub-assemblies $ 184 $ 165 Work in process 93 106 Finished goods 76 59 Total $ 353 $ 330

Goodwill and Identifiable Intan

Goodwill and Identifiable Intangible Assets	3 Months Ended
	Mar. 31, 2017
Goodwill and Identifiable Intangible Assets [Abstract]
Goodwill and Identifiable Intangible Assets	8. Goodwill and Identifiable Intangible Assets Goodwill. Electronic Systems Aerospace Systems Communication Systems Sensor Systems Consolidated Total (in millions) Goodwill (1) $ 2,687 $ 1,698 $ 1,058 $ 1,559 $ 7,002 Accumulated impairment losses (43 ) (338 ) (35 ) (26 ) (442 ) Balance at December 31, 2016 2,644 1,360 1,023 1,533 6,560 Business acquisitions (2) 100 — — 16 116 Business divestitures (3) (12 ) — — — (12 ) Foreign currency translation adjustments (4) 8 2 — 5 15 Balance at March 31, 2017 2,740 1,362 1,023 1,554 6,679 Goodwill 2,783 1,700 1,058 1,580 7,121 Accumulated impairment losses (43 ) (338 ) (35 ) (26 ) (442 ) $ 2,740 $ 1,362 $ 1,023 $ 1,554 $ 6,679 (1) The business realignment in the Electronic Systems segment resulted in a reallocation of goodwill due to changes in reporting units. Goodwill was reallocated to the affected reporting units based upon their relative fair value. The changes to reporting units did not result in a goodwill impairment of any reporting unit. (2) The increase for the Electronic Systems segment was due to the acquisition of the ETD business and the purchase price allocation adjustment for the MacH business acquisition. The increase for the Sensor Systems segment was primarily due to the OceanServer business acquisition. (3) The decrease for the Electronic Systems segment was due to the divestitures of Coleman and Aviation Jet Services during the quarterly period ended March 31, 2017. (4) The increase in the Electronic Systems segment was due to the weakening of the U.S. dollar against the British pound and the Canadian dollar during the quarterly period ended March 31, 2017. The increase in the Aerospace Systems segment was due to the weakening of the U.S. dollar against the Canadian dollar during the quarterly period ended March 31, 2017. The increase in the Sensor Systems segment was due to the weakening of the U.S. dollar against the Australian dollar, the Euro and the British pound during the quarterly period ended March 31, 2017. Identifiable Intangible Assets. Identifiable Intangible Assets. March 31, 2017 December 31, 2016 Weighted Average Amortization Period Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount (in years) (in millions) Customer contractual relationships 15 $ 412 $ 276 $ 136 $ 409 $ 269 $ 140 Technology 10 202 105 97 191 102 89 Other 18 21 12 9 21 12 9 Total 13 $ 635 $ 393 $ 242 $ 621 $ 383 $ 238 The table below presents amortization expense recorded by the Company for its identifiable intangible assets. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Amortization expense $ 10 $ 8 Based on gross carrying amounts at March 31, 2017, the Company’s estimate of amortization expense for identifiable intangible assets for the years ending December 31, 2017 through 2021 is presented in the table below. Year Ending December 31, 2017 2018 2019 2020 2021 (in millions) Estimated amortization expense $ 40 $ 38 $ 34 $ 30 $ 27

Other Current Liabilities and O

Other Current Liabilities and Other Liabilities	3 Months Ended
	Mar. 31, 2017
Other Current Liabilities and Other Liabilities [Abstract]
Other Current Liabilities and Other Liabilities	9. Other Current Liabilities and Other Liabilities The table below presents the components of other current liabilities. March 31, 2017 December 31, 2016 (in millions) Other Current Liabilities: Accrued product warranty costs $ 80 $ 68 Estimated costs in excess of estimated contract value to complete contracts in process in a loss position 74 70 Accrued interest 48 43 Accruals for pending and threatened litigation (see Note 18) (1) 45 51 Deferred revenues 36 34 Product returns allowance (2) 4 5 Other 157 160 Total other current liabilities $ 444 $ 431 (1) The quarterly period ended March 31, 2017 and the year ended December 31, 2016 included $10 million and $14 million, respectively, in connection with the EoTech matter. (2) On March 23, 2017, the Company ended the voluntary return program for various EoTech HWS products in connection with the preliminary settlement of the class action lawsuit (See Note 18). The product returns allowance, net of refund payments made to eligible owners, was $2 million at March 31, 2017. As of April 16, 2017, the Company had approved refunds at a cost of approximately $36 million, with an average refund cost per unit of $500. The table below presents the components of other liabilities. March 31, 2017 December 31, 2016 (in millions) Other Liabilities: Non-current income taxes payable (see Note 11) $ 123 $ 124 Deferred compensation 50 47 Accrued product warranty costs 36 41 Estimated contingent purchase price payable for acquired businesses (see Note 5) 31 29 Accrued workers’ compensation 29 30 Notes payable and capital lease obligations 14 13 Other 82 84 Total other liabilities $ 365 $ 368 The table below presents the changes in the Company’s accrued product warranty costs. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Accrued product warranty costs: (1) Balance at January 1 $ 109 $ 105 Acquisitions during the period 3 — Accruals for product warranties issued during the period 16 9 Settlements made during the period (12 ) (11 ) Balance at end of period $ 116 $ 103 (1) Warranty obligations incurred in connection with long-term production contracts that are accounted for under the POC cost-to-cost method are included within the contract estimates at completion and are excluded from the above amounts. The balances above include both the current and non-current amounts.

Debt

Debt	3 Months Ended
	Mar. 31, 2017
Debt [Abstract]
Debt	10. Debt The components of debt and a reconciliation to the carrying amount of long-term debt is presented in the table below. March 31, 2017 December 31, 2016 (in millions) Borrowings under Revolving Credit Facility (1) $ — $ — 5.20% Senior Notes due 2019 1,000 1,000 4.75% Senior Notes due 2020 800 800 4.95% Senior Notes due 2021 650 650 3.95% Senior Notes due 2024 350 350 3.85% Senior Notes due 2026 550 550 Principal amount of long-term debt 3,350 3,350 Unamortized discounts (8 ) (8 ) Deferred debt issue costs (16 ) (17 ) Carrying amount of long-term debt $ 3,326 $ 3,325 (1) During the quarterly period ended March 31, 2017, L3’s aggregate borrowings and repayments under the Credit Facility were $664 million. At March 31, 2017, L3 had the full availability of its $1 billion Credit Facility.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2017
Income Taxes [Abstract]
Income Taxes	11. Income Taxes The Company and its subsidiaries file income tax returns in the U.S. Federal jurisdiction, which is the Company’s primary tax jurisdiction, and various state and foreign jurisdictions. At March 31, 2017, the statutes of limitations for the Company’s U.S. Federal income tax returns for the years ended December 31, 2010 through 2015 were open. The U.S. Internal Revenue Service (IRS) commenced audits of the Company’s U.S. Federal income tax returns for the years ended 2012 and 2013. The Company cannot predict the outcome of the audits at this time. The effective income tax rate for the quarterly period ended March 31, 2017 decreased to 22.2% from 22.3% for the quarterly period ended March 25, 2016 primarily due to the benefit from the release of a valuation allowance for capital losses partially offset by a higher income tax rate on foreign earnings. At March 31, 2017, the Company anticipates that unrecognized tax benefits will decrease by approximately $9 million over the next 12 months due to the potential resolution of unrecognized tax benefits involving several jurisdictions and tax periods. The actual amount of the decrease over the next 12 months could vary significantly depending on the ultimate timing and nature of any settlements. Current and non-current income taxes payable include accrued potential interest of $11 million ($6 million after income taxes) at March 31, 2017 and $11 million ($7 million after income taxes) at December 31, 2016, and potential penalties of $8 million at March 31, 2017 and December 31, 2016.

Accumulated Other Comprehensive

Accumulated Other Comprehensive (Loss) Income (AOCI)	3 Months Ended
	Mar. 31, 2017
Accumulated Other Comprehensive (Loss) Income (AOCI) [Abstract]
Accumulated Other Comprehensive (Loss) Income (AOCI)	12. Accumulated Other Comprehensive (Loss) Income (AOCI) The changes in the AOCI balances, including amounts reclassified from AOCI into net income, are presented in the table below. Foreign currency translation Unrealized gains (losses) on hedging instruments Unrecognized (losses) gains and prior service cost, net Total accumulated other comprehensive loss (in millions) Balance at December 31, 2016 $ (178 ) $ 6 $ (554 ) $ (726 ) Other comprehensive income before reclassifications, net of tax 19 — — 19 Amounts reclassified from AOCI, net of tax — — 9 9 Net current period other comprehensive income 19 — 9 28 Balance at March 31, 2017 $ (159 ) $ 6 $ (545 ) $ (698 ) Balance at December 31, 2015 $ (101 ) $ (8 ) $ (465 ) $ (574 ) Other comprehensive income before reclassifications, net of tax 1 6 — 7 Amounts reclassified from AOCI, net of tax — 1 8 9 Net current period other comprehensive income 1 7 8 16 Balance at March 25, 2016 $ (100 ) $ (1 ) $ (457 ) $ (558 ) Further details regarding the amounts reclassified from AOCI into net income are presented in the table below. Amount Reclassified from AOCI (a) Affected Line Item in the Unaudited Condensed Consolidated Statements of Operations First Quarter Ended Details About AOCI Components March 31, 2017 March 25, 2016 (in millions) Loss on hedging instruments $ — $ (3 ) Cost of sales-products — (3 ) Income from continuing operations before income taxes — 2 Provision for income taxes $ — $ (1 ) Income from continuing operations Amortization of defined benefit pension items: Net loss $ (15 ) $ (12 ) (b) (15 ) (12 ) Income from continuing operations before income taxes 6 4 Provision for income taxes $ (9 ) $ (8 ) Income from continuing operations Total reclassification for the period $ (9 ) $ (9 ) Income from continuing operations (a) Amounts in parenthesis indicate charges to the unaudited condensed consolidated statements of operations. (b) Amounts related to pension and postretirement benefit plans were reclassified from AOCI and recorded as a component of net periodic benefit cost (see Note 19 for additional information).

Equity

Equity	3 Months Ended
	Mar. 31, 2017
Equity [Abstract]
Equity	13. Equity On December 4, 2014, L3’s Board of Directors approved a share repurchase program that authorizes L3 to repurchase up to $1.5 billion of its common stock through June 30, 2017. Repurchases of L3’s common stock are made from time to time at management’s discretion in accordance with applicable U.S. Federal securities laws. The timing and actual number of shares to be repurchased in the future will depend on a variety of factors, including, but not limited to, the Company’s financial position, earnings, legal requirements, other investment opportunities (including acquisitions) and market conditions. The Company did not repurchase any shares of common stock from January 1, 2017 through March 31, 2017. All share repurchases of L3’s common stock have been recorded as treasury shares. At March 31, 2017, the remaining dollar value of authorization under the December 4, 2014 share repurchase program was $433 million. From April 1, 2017 through April 21, 2017, L3 repurchased 66,462 shares of its common stock at an average price of $165.48 per share for an aggregate amount of $11 million. On February 13, 2017, L3’s Board of Directors declared a quarterly cash dividend of $0.75 per share, paid on March 15, 2017 to shareholders of record at the close of business on March 1, 2017. During the quarterly period ended March 31, 2017, the Company paid $61 million of cash dividends, including a $2 million net reduction of previously accrued dividends for employee held stock awards.

L3's Earnings Per Share

L3's Earnings Per Share	3 Months Ended
	Mar. 31, 2017
L3's Earnings Per Share [Abstract]
L3's Earnings Per Share	14. L3’s Earnings Per Share A reconciliation of basic and diluted earnings per share (EPS) is presented in the table below. First Quarter Ended March 31, 2017 March 25, 2016 (in millions, except per share data) Reconciliation of net income: Net income $ 168 $ 230 Net income from continuing operations attributable to noncontrolling interests (4 ) (3 ) Net income attributable to L3’s common shareholders $ 164 $ 227 Earnings attributable to L3’s common shareholders: Continuing operations $ 164 $ 164 Discontinued operations, net of income tax — 63 Net income attributable to L3’s common shareholders $ 164 $ 227 Earnings per share attributable to L3’s common shareholders: Basic: Weighted average common shares outstanding 77.7 77.8 Basic earnings per share: Continuing operations $ 2.11 $ 2.11 Discontinued operations, net of income tax — 0.81 Net income $ 2.11 $ 2.92 Diluted: Common and potential common shares: Weighted average common shares outstanding 77.7 77.8 Assumed exercise of stock options 2.8 2.0 Unvested restricted stock awards 0.8 1.1 Employee stock purchase plan contributions 0.1 0.1 Performance unit awards 0.1 0.1 Assumed purchase of common shares for treasury (2.2 ) (2.1 ) Common and potential common shares 79.3 79.0 Diluted earnings per share: Continuing operations $ 2.07 $ 2.08 Discontinued operations, net of income tax — 0.79 Net income $ 2.07 $ 2.87 The computation of diluted EPS excludes shares for stock options, restricted stock awards and performance unit awards contributions of 0.3 million and 1.2 million for the quarterly periods ended March 31, 2017 and March 25, 2016, respectively, as they were anti-dilutive.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2017
Fair Value Measurements [Abstract]
Fair Value Measurements	15. Fair Value Measurements L3 applies the accounting standards for fair value measurements to all of the Company’s assets and liabilities that are measured and recorded at fair value. Fair value is defined as the price that would be received for an asset or the exit price that would be paid to transfer a liability in the principal or most advantageous market in an orderly transaction between market participants. The standards establish a fair value hierarchy that gives the highest priority to observable inputs and the lowest priority to unobservable inputs. The following table presents the fair value hierarchy level for each of the Company’s assets and liabilities that are measured and recorded at fair value on a recurring basis. March 31, 2017 December 31, 2016 Description Level 1 (1) Level 2 (2) Level 3 (3) Level 1 (1) Level 2 (2) Level 3 (3) (in millions) Assets Cash equivalents $ 12 $ — $ — $ 104 $ — $ — Derivatives (foreign currency forward contracts) — 11 — — 12 — Total assets $ 12 $ 11 $ — $ 104 $ 12 $ — Liabilities Derivatives (foreign currency forward contracts) $ — $ 3 $ — $ — $ 6 $ — Contingent consideration (4) — — 31 — — 29 Total liabilities $ — $ 3 $ 31 $ — $ 6 $ 29 (1) Level 1 is based on quoted market prices available in active markets for identical assets or liabilities as of the reporting date. Cash equivalents are primarily held in registered money market funds, which are valued using quoted market prices. (2) Level 2 is based on pricing inputs other than quoted prices in active markets, which are either directly or indirectly observable. The fair value is determined using a valuation model based on observable market inputs, including quoted foreign currency forward exchange rates and consideration of non-performance risk. (3) Level 3 is based on pricing inputs that are not observable and not corroborated by market data. (4) The contingent consideration liability represents the future potential earn-out payments relating to the MacH acquisition. The fair value of the contingent consideration liability is based on a Monte Carlo Simulation of the aggregate revenue of MacH for the three-year period ending December 31, 2019. The significant unobservable inputs used in calculating the fair value of the contingent consideration include: (i) projected revenues of the MacH acquired business, (ii) company specific risk premium, which is a component of the discount rate applied to the revenue projections, (iii) and volatility. The fair value of the contingent consideration for potential earn-out payments is reassessed quarterly, including an analysis of the significant inputs used in the evaluation, as well as the accretion of the present value discount. Changes are reflected within cost of sales in the consolidated statements of operations. The table below presents the changes to contingent consideration obligations during the quarterly period ended March 31, 2017. March 31, 2017 (in millions) Balance at beginning of period $ 29 Changes in fair value of contingent consideration, net 2 Balance at end of period $ 31

Financial Instruments

Financial Instruments	3 Months Ended
	Mar. 31, 2017
Financial Instruments [Abstract]
Financial Instruments	16. Financial Instruments At March 31, 2017 and December 31, 2016, the Company’s financial instruments consisted primarily of cash and cash equivalents, billed receivables, trade accounts payable, Senior Notes and foreign currency forward contracts. The carrying amounts of cash and cash equivalents, billed receivables and trade accounts payable are representative of their respective fair values because of the short-term maturities or the expected settlement dates of these instruments. The carrying amounts and estimated fair values of the Company’s other financial instruments are presented in the table below. March 31, 2017 December 31, 2016 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value (in millions) Senior Notes (1) $ 3,326 $ 3,542 $ 3,325 $ 3,526 Foreign currency forward contracts (2) $ 8 $ 8 $ 6 $ 6 (1) The Company measures the fair value of its Senior Notes using Level 2 inputs based primarily on current market yields for its existing debt traded in the secondary market. (2) The Company measures the fair values of foreign currency forward contracts based on forward exchange rates. See Note 17 for additional disclosures regarding the notional amounts and fair values of foreign currency forward contracts.

Derivative Financial Instrument

Derivative Financial Instruments	3 Months Ended
	Mar. 31, 2017
Derivative Financial Instruments [Abstract]
Derivative Financial Instruments	17. Derivative Financial Instruments The Company’s derivative financial instruments include foreign currency forward contracts, which are entered into for risk management purposes. Foreign Currency Forward Contracts. Currency Notional Amounts (in millions) U.S. dollar $ 109 Euro 98 Canadian dollar 73 British pound 35 Other 16 Total $ 331 At March 31, 2017, the Company’s foreign currency forward contracts had maturities through 2021. The table below presents the location of the Company’s derivative instruments recorded at fair value on the condensed consolidated balance sheets. March 31, 2017 December 31, 2016 Other Current Assets Other Assets Other Current Liabilities Other Liabilities Other Current Assets Other Assets Other Current Liabilities Other Liabilities (in millions) Derivatives designated as hedging instruments: Foreign currency forward contracts (1) $ 9 $ 2 $ 3 $ — $ 10 $ 2 $ 6 $ — Total derivative instruments $ 9 $ 2 $ 3 $ — $ 10 $ 2 $ 6 $ — (1) See Note 15 for a description of the fair value hierarchy related to the Company’s foreign currency forward contracts. The effect from foreign currency forward contracts on the unaudited condensed consolidated statements of operations was a pre-tax loss of $3 million for the quarterly period ended March 25, 2016. At March 31, 2017, the estimated net amount of existing gains that are expected to be reclassified into income within the next 12 months was $6 million.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2017
Commitments and Contingencies [Abstract]
Commitments and Contingencies	18. Commitments and Contingencies Procurement Regulations A substantial majority of the Company’s revenues are generated from providing products and services under legally binding agreements or contracts with the U.S. Government, foreign government customers and state and local governments. U.S. Government contracts are subject to extensive legal and regulatory requirements, and, from time to time, agencies of the U.S. Government investigate whether such contracts were and are being conducted in accordance with these requirements. The Company is currently cooperating with the U.S. Government on several investigations from which civil, criminal or administrative proceedings have or could result and give rise to fines, penalties, compensatory and treble damages, restitution and/or forfeitures, including investigations into the pricing of certain contracts entered into by the Communication Systems segment. The Company does not currently anticipate that any of these investigations will have a material adverse effect, individually or in the aggregate, on its consolidated financial position, results of operations or cash flows. However, under U.S. Government regulations, an indictment of the Company by a federal grand jury, or an administrative finding against the Company as to its present responsibility to be a U.S. Government contractor or subcontractor, could result in the Company being suspended for a period of time from eligibility for awards of new government contracts or task orders or in a loss of export privileges. A conviction, or an administrative finding against the Company that satisfies the requisite level of seriousness, could result in debarment from contracting with the federal government for a specified term. In addition, all of the Company’s U.S. Government contracts: (1) are subject to audit and various pricing and cost controls, (2) include standard provisions for termination for the convenience of the U.S. Government or for default and (3) are subject to cancellation if funds for contracts become unavailable. Foreign government contracts generally include comparable provisions relating to terminations for convenience or default, as well as other procurement clauses relevant to the foreign government. Litigation Matters The Company is also subject to litigation, proceedings, claims or assessments and various contingent liabilities incidental to its businesses, including those specified below. Furthermore, in connection with certain business acquisitions, the Company has assumed some or all claims against, and liabilities of, such acquired businesses, including both asserted and unasserted claims and liabilities. In accordance with the accounting standard for contingencies, the Company records a liability when management believes that it is both probable that a liability has been incurred and the Company can reasonably estimate the amount of the loss. Generally, the loss is recorded at the amount the Company expects to resolve the liability. The estimated amounts of liabilities recorded for pending and threatened litigation are disclosed in Note 9. Amounts recoverable from insurance contracts or third parties are recorded as assets when deemed probable. At March 31, 2017, the Company recorded approximately $34.5 million of receivables for recoveries from insurance contracts or third parties in connection with the amount of liabilities recorded for pending and threatened litigation. Legal defense costs are expensed as incurred. The Company believes it has recorded adequate provisions for its litigation matters. The Company reviews these provisions to reflect the impact of negotiations, settlements, rulings, advice of legal counsel and other information and events pertaining to a particular matter. While it is reasonably possible that an unfavorable outcome may occur in one or more of the following matters, unless otherwise stated below, the Company believes that it is not probable that a loss has been incurred in any of these matters. With respect to the litigation matters below for which it is reasonably possible that an unfavorable outcome may occur, an estimate of loss or range of loss is disclosed when such amount or amounts can be reasonably estimated. Although the Company believes that it has valid defenses with respect to legal matters and investigations pending against it, the results of litigation can be difficult to predict, particularly those involving jury trials. Therefore, it is possible that one or more of the following or other contingencies could have a material impact on the financial position, results of operations or cash flows of the Company in future periods. EoTech Class Actions. Securities Class Action. 401(k) Plan Class Action Derivative Action. HVC Alkmaar

Pension and Other Postretiremen

Pension and Other Postretirement Benefits	3 Months Ended
	Mar. 31, 2017
Pension and Other Postretirement Benefits [Abstract]
Pension and Other Postretirement Benefits	19. Pension and Other Postretirement Benefits The following table summarizes the components of net periodic benefit cost for the Company’s pension and other postretirement benefit plans. Pension Plans Postretirement Benefit Plans First Quarter Ended First Quarter Ended March 31, 2017 March 25, 2016 March 31, 2017 March 25, 2016 (in millions) Components of net periodic benefit cost: Service cost $ 29 $ 27 $ 1 $ 1 Interest cost 35 35 1 1 Expected return on plan assets (53 ) (51 ) (1 ) (1 ) Amortization of prior service costs (credits) — — — (1 ) Amortization of net loss 16 13 (1 ) — Net periodic benefit cost $ 27 $ 24 $ — $ — Contributions.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2017
Stock-Based Compensation [Abstract]
Stock-Based Compensation	20. Stock-Based Compensation During the quarterly period ended March 31, 2017, the Company granted stock-based awards under the Amended and Restated 2008 Long Term Performance Plan in the form of stock options, restricted stock units and performance units. The stock-based compensation awards granted during the quarterly period ended March 31, 2017 are further discussed below. Stock Options. Expected holding period (in years) 5.2 Expected volatility 20.1 % Expected dividend yield 2.0 % Risk-free interest rate 2.0 % Restricted Stock Units. Performance Units.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	3 Months Ended
	Mar. 31, 2017
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	21. Supplemental Cash Flow Information First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Interest paid on outstanding debt $ 37 $ 36 Income tax payments $ 20 $ 12 Income tax refunds $ 5 $ 1

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2017
Segment Information [Abstract]
Segment Information	22. Segment Information The Company has four reportable segments, which are described in Note 1. The Company evaluates the performance of its operating segments and reportable segments based on their sales, operating income and operating margin. Corporate expenses are allocated to the Company’s operating segments using an allocation methodology prescribed by U.S. Government regulations for government contractors. Accordingly, segment results include all costs and expenses, except for goodwill impairment charges and certain other items that are excluded by management for purposes of evaluating the operating performance of the Company’s business segments. The tables below present net sales, operating income, depreciation and amortization and total assets by reportable segment. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Net Sales: Aerospace Systems $ 1,045 $ 1,007 Electronic Systems 760 615 Communication Systems 543 477 Sensor Systems 354 290 Elimination of intercompany sales (33 ) (36 ) Consolidated total $ 2,669 $ 2,353 Operating Income: Aerospace Systems $ 69 $ 106 Electronic Systems 91 85 Communication Systems 43 51 Sensor Systems 50 10 Consolidated total $ 253 $ 252 Depreciation and amortization: Aerospace Systems $ 13 $ 13 Electronic Systems 18 14 Communication Systems 12 12 Sensor Systems 11 11 Consolidated total $ 54 $ 50 March 31, 2017 December 31, 2016 (in millions) Total Assets: Electronic Systems $ 4,576 $ 4,369 Aerospace Systems 2,776 2,535 Communication Systems 2,099 2,031 Sensor Systems 2,482 2,433 Corporate 231 497 Consolidated total $ 12,164 $ 11,865

Severance and Restructuring Cos

Severance and Restructuring Costs	3 Months Ended
	Mar. 31, 2017
Severance and Restructuring Costs [Abstract]
Severance and Restructuring Costs	23. Severance and Restructuring Costs Consistent with the Company’s strategy to continuously improve its cost structure and right-size its businesses, especially in view of U.S. defense budget constraints, L3 is completing employment reduction actions across several of its businesses to reduce both direct and indirect costs, including overhead and general and administrative costs. As a result of these initiatives and due to the impact of U.S. defense budget constraints at certain affected business units, the Company recorded a total of $14 million of severance and restructuring costs, with respect to approximately 200 employees during the quarterly period ended March 31, 2017. During the year ended December 31, 2016, the Company recorded a total of $17 million of severance and restructuring costs with respect to approximately 700 employees. Severance and restructuring costs are reported within cost of sales on the unaudited condensed consolidated statements of operations. The remaining balance to be paid in connection with these initiatives was $19 million at March 31, 2017 and $9 million at December 31, 2016, which is expected to be paid primarily by the end of 2017. Severance and restructuring costs incurred by reportable segment are presented in the table below. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Reportable Segment Electronic Systems $ 3 $ — Aerospace Systems — — Communication Systems 9 1 Sensor Systems 2 1 Consolidated $ 14 $ 2

Condensed Combining Financial I

Condensed Combining Financial Information of L3 and Its Subsidiaries	3 Months Ended
	Mar. 31, 2017
Condensed Combining Financial Information of L3 and Its Subsidiaries
Condensed Combining Financial Information of L3 and Its Subsidiaries	24. Condensed Combining Financial Information of L3 and Its Subsidiaries The debt of L3, including the Senior Notes and borrowings under amounts drawn against the Credit Facility, are guaranteed, on a joint and several, full and unconditional basis, by certain of its domestic subsidiaries (the “Guarantor Subsidiaries”). See Note 9 to the audited consolidated financial statements for the year ended December 31, 2016, included in the Company’s Annual Report on Form 10-K for additional information. The foreign subsidiaries and certain domestic subsidiaries of L3 (the “Non-Guarantor Subsidiaries”) do not guarantee the debt of L3. None of the debt of L3 has been issued by its subsidiaries. Under the terms of the indentures governing the Senior Notes, the guarantees of the Senior Notes will automatically and unconditionally be released and discharged: (1) upon the release of all guarantees of all other outstanding indebtedness of L3, or (2) upon the determination that such guarantor is no longer a “domestic subsidiary.” In addition, the guarantees of the Senior Notes will be automatically and unconditionally released and discharged in the event of a sale or other disposition of all of the assets of any guarantor, by way of merger, consolidation or otherwise, or a sale of all of the capital stock of such guarantor. There are no restrictions on the payment of dividends from the Guarantor Subsidiaries to L3. On December 31, 2016, the Company completed an internal reorganization to eliminate its holding company structure. Pursuant to the reorganization, L-3 Communications Holdings, Inc. was merged (the Merger) with and into L-3 Communications Corporation (L-3 Corp), with L-3 Corp being the surviving entity in the Merger (the Surviving Entity). Immediately following the completion of the Merger, the name of the Surviving Entity was changed to L3 Technologies, Inc. For more information on the Merger, see Note 1 in the Company’s annual report on Form 10-K for the year ended December 31, 2016. The following unaudited condensed combining financial information presents the results of operations, financial position and cash flows of: (1) L3 excluding its consolidated subsidiaries (the Parent), (2) the Guarantor Subsidiaries, (3) the Non-Guarantor Subsidiaries and (4) the eliminations to arrive at the information for L3 on a consolidated basis. As a result of the Merger, prior year amounts have been recast to conform to the current year presentation. L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in miilions) Condensed Combining Balance Sheets: At March 31, 2017: Current assets: Cash and cash equivalents $ 58 $ 1 $ 195 $ (24 ) $ 230 Billed receivables, net 247 353 202 — 802 Contracts in process 733 1,260 261 — 2,254 Other current assets 246 227 113 — 586 Total current assets 1,284 1,841 771 (24 ) 3,872 Goodwill 2,385 3,099 1,195 — 6,679 Other assets 695 611 307 — 1,613 Investment in and amounts due from consolidated subsidiaries 6,074 4,741 — (10,815 ) — Total assets $ 10,438 $ 10,292 $ 2,273 $ (10,839 ) $ 12,164 Current liabilities $ 811 $ 934 $ 508 $ (24 ) $ 2,229 Amounts due to consolidated subsidiaries — — 289 (289 ) — Other long-term liabilities 1,570 204 33 — 1,807 Long-term debt 3,326 — — — 3,326 Total liabilities 5,707 1,138 830 (313 ) 7,362 L3 shareholders’ equity 4,731 9,154 1,443 (10,597 ) 4,731 Noncontrolling interests — — — 71 71 Total equity 4,731 9,154 1,443 (10,526 ) 4,802 Total liabilities and equity $ 10,438 $ 10,292 $ 2,273 $ (10,839 ) $ 12,164 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) At December 31, 2016: Current assets: Cash and cash equivalents $ 291 $ 1 $ 207 $ (136 ) $ 363 Billed receivables, net 261 285 185 — 731 Contracts in process 694 1,125 236 — 2,055 Other current assets 236 187 125 — 548 Total current assets 1,482 1,598 753 (136 ) 3,697 Goodwill 2,380 3,007 1,173 — 6,560 Other assets 705 591 312 — 1,608 Investment in and amounts due from consolidated subsidiaries 5,649 5,650 — (11,299 ) — Total assets $ 10,216 $ 10,846 $ 2,238 $ (11,435 ) $ 11,865 Current liabilities $ 789 $ 1,022 $ 460 $ (136 ) $ 2,135 Amounts due to consolidated subsidiaries — — 284 (284 ) — Other long-term liabilities 1,549 200 32 — 1,781 Long-term debt 3,325 — — — 3,325 Total liabilities 5,663 1,222 776 (420 ) 7,241 L3 shareholders’ equity 4,553 9,624 1,462 (11,086 ) 4,553 Noncontrolling interests — — — 71 71 Total equity 4,553 9,624 1,462 (11,015 ) 4,624 Total liabilities and equity $ 10,216 $ 10,846 $ 2,238 $ (11,435 ) $ 11,865 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) Condensed Combining Statements of Operations: For the quarter ended March 31, 2017: Total net sales $ 862 $ 1,507 $ 373 $ (73 ) $ 2,669 Total cost of sales (777 ) (1,399 ) (313 ) 73 (2,416 ) Operating income 85 108 60 — 253 Interest expense (42 ) — — — (42 ) Interest and other income, net 3 — 2 — 5 Income from continuing operations before income taxes 46 108 62 — 216 Provision for income taxes (10 ) (24 ) (14 ) — (48 ) Equity in net income of consolidated subsidiaries 128 — — (128 ) — Net income 164 84 48 (128 ) 168 Net income attributable to noncontrolling interests — — — (4 ) (4 ) Net income attributable to L3 $ 164 $ 84 $ 48 $ (132 ) $ 164 Comprehensive income attributable to L3 $ 192 $ 84 $ 68 $ (152 ) $ 192 For the quarter ended March 25, 2016: Total net sales $ 822 $ 1,185 $ 409 $ (63 ) $ 2,353 Total cost of sales (739 ) (1,068 ) (357 ) 63 (2,101 ) Operating income 83 117 52 — 252 Interest expense (41 ) — — — (41 ) Interest and other income, net 3 — 1 — 4 Income from continuing operations before income taxes 45 117 53 — 215 Provision for income taxes (10 ) (26 ) (12 ) — (48 ) Equity in net income of consolidated subsidiaries 192 — — (192 ) — Income from continuing operations 227 91 41 (192 ) 167 Income from discontinued operations, net of income tax — 63 — — 63 Net income 227 154 41 (192 ) 230 Net income attributable to noncontrolling interests — — — (3 ) (3 ) Net income attributable to L3 $ 227 $ 154 $ 41 $ (195 ) $ 227 Comprehensive income attributable to L3 $ 243 $ 162 $ 41 $ (203 ) $ 243 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) Condensed Combining Statements of Cash Flows For the quarterly period ended March 31, 2017: Operating activities: Net cash from (used in) operating activities from continuing operations $ 144 $ (85 ) 67 $ (41 ) $ 85 Investing activities: Business acquisitions, net of cash acquired (139 ) — — — (139 ) Proceeds from sale of businesses, net of closing date cash balances 15 — 1 — 16 Other investing activities (16 ) (17 ) (3 ) — (36 ) Net cash used in investing activities from continuing operations (140 ) (17 ) (2 ) — (159 ) Financing activities: Dividends paid on L3's common stock (61 ) — — — (61 ) Other financing activities (176 ) 102 (81 ) 153 (2 ) Net cash (used in) from financing activities from continuing operations (237 ) 102 (81 ) 153 (63 ) Effect of foreign currency exchange rate changes on cash — — 4 — 4 Net decrease in cash (233 ) — (12 ) 112 (133 ) Cash and cash equivalents, beginning of the period 291 1 207 (136 ) 363 Cash and cash equivalents, end of the period $ 58 $ 1 $ 195 $ (24 ) $ 230 For the quarterly period ended March 25, 2016: Operating activities: Net cash from (used in) operating activities from continuing operations $ 46 $ 117 $ (32 ) $ (19 ) $ 112 Investing activities: Business acquisitions, net of cash acquired (27 ) — — — (27 ) Proceeds from sale of businesses, net of closing date cash balance 576 — — — 576 Other investing activities 3 (12 ) (10 ) — (19 ) Net cash from (used in) investing activities from continuing operations 552 (12 ) (10 ) — 530 Financing activities: Common stock repurchased (198 ) — — — (198 ) Dividends paid on L3's common stock (58 ) — — — (58 ) Other financing activities (130 ) (46 ) 66 107 (3 ) Net cash (used in) from financing activities from continuing operations (386 ) (46 ) 66 107 (259 ) Net decrease in cash and cash equivalents of discontinued operations — (56 ) — — (56 ) Net increase in cash 212 3 24 88 327 Cash and cash equivalents, beginning of the period 137 — 165 (95 ) 207 Cash and cash equivalents, end of the period $ 349 $ 3 $ 189 $ (7 ) $ 534

Basis of Presentation (Policies

Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2017
Basis of Presentation [Abstract]
Principles of Consolidation and Reporting	Principles of Consolidation and Reporting The accompanying financial statements comprise the consolidated financial statements of L3. The consolidated financial statements of the Company include all wholly-owned and majority-owned subsidiaries. All significant intercompany transactions are eliminated in consolidation. Investments in equity securities, joint ventures and limited liability corporations over which the Company has significant influence but does not have voting control are accounted for using the equity method. Investments over which the Company does not have significant influence are accounted for using the cost method. For the classification of contract related assets and liabilities, the Company uses the duration of the related contract or program as its operating cycle, which may be longer than one year, and classifies them as current. Certain reclassifications have been made to conform prior-year amounts to the current-year presentation. The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X of the Securities and Exchange Commission (SEC). Accordingly, they do not include all of the disclosures required by U.S. GAAP for a complete set of annual audited financial statements. The December 31, 2016 condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by U.S. GAAP. In the opinion of management, all adjustments (consisting of normal and recurring adjustments) considered necessary for a fair statement of the results for the interim periods presented have been included. The results of operations for the interim periods are not necessarily indicative of results for the full year. It is generally the Company’s established practice to close its books for the quarters ending March, June and September on the Friday preceding the end of the calendar quarter. The interim unaudited condensed consolidated financial statements included herein have been prepared and are labeled based on that convention. The Company closes its books for annual periods on December 31 regardless of what day it falls on.
Accounting Estimates	Accounting Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of sales and costs of sales during the reporting period. The most significant of these estimates and assumptions for L3 relate to contract revenue, profit and loss recognition, fair values of assets acquired and liabilities assumed in business combinations, market values for inventories reported at lower of cost or market, pension and post-retirement benefit obligations, stock-based employee compensation expense, income taxes, including the valuations of deferred tax assets, litigation reserves and environmental obligations, accrued product warranty costs, useful lives and valuation of recorded amounts of long-lived assets, identifiable intangible assets and goodwill. Changes in estimates are reflected in the periods during which they become known. Actual amounts may differ from these estimates and could differ materially. Revisions or adjustments to estimates for a contract’s revenue, estimated costs at completion and estimated profit or loss are often required as work progresses under a contract, as experience is gained, as facts and circumstances change and as new information is obtained, even though the scope of work required under the contract may not change. Revisions or adjustments may also be required if contract modifications occur. The impact of revisions in profit (loss) estimates for all types of contracts subject to percentage-of-completion (POC) accounting are recognized on a cumulative catch-up basis in the period in which the revisions are made. The revisions in contract estimates, if significant, can materially affect the Company’s results of operations and cash flows, as well as reduce the valuations of receivables and inventories, and in some cases result in liabilities to complete contracts in a loss position. Aggregate net changes in contract estimates amounted to increases of $41 million, or 16%, of operating income ($0.33 per diluted share) for the quarterly period ended March 31, 2017, and increases of $56 million, or 22%, of operating income ($0.46 per diluted share) for the quarterly period ended March 25, 2016.
Revenue Recognition	Revenue Recognition Substantially all of the Company’s sales are generated from written contractual (revenue) arrangements. The sales price for the Company’s revenue arrangements are either fixed-price, cost-plus or time-and-material type. Depending on the contractual scope of work, the Company utilizes either contract accounting standards or accounting standards for revenue arrangements with commercial customers to account for these contracts. Approximately 50% of the Company’s net sales in 2016 were accounted for under contract accounting standards, of which approximately 41% were fixed-price type contracts and approximately 9% were cost-plus type contracts. For contracts that are accounted for under contract accounting standards, sales and profits are recognized based on: (1) a POC method of accounting (fixed-price type contracts), (2) allowable costs incurred plus the estimated profit on those costs (cost-plus type contracts), or (3) direct labor hours expended multiplied by the contractual fixed rate per hour plus incurred costs for material (time-and-material type contracts). Sales and profits on fixed-price type contracts that are covered by contract accounting standards are substantially recognized using POC methods of accounting. Sales and profits on fixed-price production contracts under which units are produced and delivered in a continuous or sequential process are recorded as units are delivered based on their contractual selling prices (the “units-of-delivery” method). Sales and profits on each fixed-price production contract under which units are not produced and delivered in a continuous or sequential process, or under which a relatively few number of units are produced, are recorded based on the ratio of actual cumulative costs incurred to the total estimated costs at completion of the contract, multiplied by the total estimated contract revenue, less cumulative sales recognized in prior periods (the “cost-to-cost” method). Under both POC methods of accounting, a single estimated total profit margin is used to recognize profit for each contract over its entire period of performance, which can exceed one year. Losses on contracts are recognized in the period in which they become evident. Amounts representing contract change orders or claims are included in sales only when they can be reliably estimated and their realization is reasonably assured. The impact of revisions of contract estimates, which may result from contract modifications, performance or other reasons, are recognized on a cumulative catch-up basis in the period in which the revisions are made. Sales and profits on cost-plus type contracts that are covered by contract accounting standards are recognized as allowable costs are incurred on the contract, at an amount equal to the allowable costs plus the estimated profit on those costs. The estimated profit on a cost-plus type contract is fixed or variable based on the contractual fee arrangement types. Incentive and award fees are the primary variable fee contractual arrangement types for the Company. Incentive and award fees on cost-plus type contracts are included as an element of total estimated contract revenues and are recorded as sales when a basis exists for the reasonable prediction of performance in relation to established contractual targets and the Company is able to make reasonably dependable estimates for them. Sales and profits on time-and-material type contracts are recognized on the basis of direct labor hours expended multiplied by the contractual fixed rate per hour, plus the actual costs of materials and other direct non-labor costs. Sales on arrangements for (1) fixed-price type contracts that require the Company to perform services that are not related to the production of tangible assets (Fixed-Price Service Contracts) and (2) certain commercial customers are recognized in accordance with accounting standards for revenue arrangements with commercial customers. Sales for the Company’s businesses whose customers are primarily commercial business enterprises are substantially all generated from single element revenue arrangements. Sales are recognized when there is persuasive evidence of an arrangement, delivery has occurred or services have been performed, the selling price to the buyer is fixed or determinable and collectability is reasonably assured. Sales for Fixed-Price Service Contracts that do not contain measurable units of work performed are generally recognized on a straight-line basis over the contractual service period, unless evidence suggests that the revenue is earned, or obligations fulfilled, in a different manner. Sales for Fixed-Price Service Contracts that contain measurable units of work performed are generally recognized when the units of work are completed. Sales and profit on cost-plus and time-and-material type contracts within the scope of accounting standards for revenue arrangements with commercial customers are recognized in the same manner as those within the scope of contract accounting standards, except for incentive and award fees. Cost-based incentive fees are recognized when they are realizable in the amount that would be due under the contractual termination provisions as if the contract was terminated. Performance based incentive fees and award fees are recorded as sales when objective evidence exists that the fees have been earned. For a more complete discussion of these estimates and assumptions, see the Annual Report on Form 10-K for the year ended December 31, 2016.

New Accounting Standards Impl35

New Accounting Standards Implemented (Policies)	3 Months Ended
	Mar. 31, 2017
New Accounting Standards Implemented [Abstract]
New Accounting Standards Implemented	In January 2017, the Financial Accounting Standards Board (FASB) issued ASU 2017-04, Simplifying the Test for Goodwill Impairment

Accounting Standards Issued a36

Accounting Standards Issued and Not Yet Implemented (Policies)	3 Months Ended
	Mar. 31, 2017
Accounting Standards Issued and Not Yet Implemented [Abstract]
Accounting Standards Issued and Not Yet Implemented	In March 2017, the FASB issued ASU 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost In January 2017, the FASB issued ASU 2017-01, Clarifying the Definition of a Business In February 2016, the FASB issued ASU 2016-02, Leases In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers The Company will adopt the standard as of January 1, 2018, using the modified retrospective transition method and is currently evaluating the expected impact of the adoption on its consolidated financial statements, and related disclosures. Under the modified retrospective transition method, the Company will be required to calculate and record the cumulative effect of adopting the new standard as of January 1, 2018, in the Company’s Quarterly Report on Form 10-Q for the first quarter of 2018. The Company expects to estimate the cumulative effect of adopting the new standard as of January 1, 2018 in the second half of 2017 based on expected contracts in process at December 31, 2017. The Company has made progress toward completing its evaluation of the potential changes from adopting this new standard on its financial reporting and disclosures. Specifically, the Company has evaluated the impact of the standard on its various revenue streams. Based on progress made to date, the Company expects to recognize revenue over time on most of its contracts that are covered by current contract accounting standards by using cost inputs to measure progress toward the completion of its performance obligations, which is similar to the POC cost-to-cost method currently used on the majority of these contracts. Accordingly, the Company expects the adoption of this standard to primarily impact certain contracts currently covered by contract accounting standards that recognize revenue using the POC units-of-delivery method. Approximately 20% of the Company’s net sales used the POC units-of-delivery method to recognize revenue in 2016. Upon adoption, the Company expects to recognize revenue earlier in the performance period as costs are incurred, as opposed to when units are delivered, on some of these contracts that currently use the POC units-of-delivery method to recognize revenue. Additionally, the Company has also made progress on drafting its accounting policies affected by this standard, the redesign of internal controls over financial reporting related to the standard, as well as evaluating the expanded disclosure requirements. The Company expects to complete the evaluation of the impact of the accounting and disclosure changes on its business processes, controls and systems during the first half of 2017, and implement any changes to such business processes, controls and systems over the remainder of 2017. Other accounting standard updates effective for interim and annual periods beginning after December 31, 2017 are not expected to have an impact on the Company’s financial position, results of operations or cash flows.

Acquisitions and Divestitures (

Acquisitions and Divestitures (Tables)	3 Months Ended
	Mar. 31, 2017
Net Sales and Income Before Income Taxes for OceanServer and ETD	Net sales and income before income taxes for OceanServer and the ETD business, included in L3’s unaudited condensed consolidated statement of operations for the quarterly period ended March 31, 2017, are presented in the table below. First Quarter Ended March 31, 2017 (in millions) Net sales $ 19 Income before income taxes $ 1
Unaudited Pro Forma Statements of Operations Data	The following unaudited pro forma Statements of Operations data present the combined results of the Company and its business acquisitions completed during the quarterly period ended March 31, 2017 and the year ended December 31, 2016, assuming that the business acquisitions completed during 2017 and 2016 had occurred on January 1, 2016 and January 1, 2015, respectively. The unaudited pro forma Statements of Operations data below include adjustments for additional amortization expense related to acquired intangible assets, depreciation and estimated reduction to interest income assuming the 2017 and 2016 acquisitions had occurred on January 1, 2016 and January 1, 2015, respectively. First Quarter Ended March 31, 2017 March 25, 2016 (in millions, except per share data) Pro forma net sales $ 2,672 $ 2,400 Pro forma income from continuing operations attributable to L3 $ 164 $ 165 Pro forma net income attributable to L3 $ 164 $ 228 Pro forma diluted earnings per share from continuing operations $ 2.07 $ 2.10 Pro forma diluted earnings per share $ 2.07 $ 2.89
NSS [Member]
Statement of Operations Data Classified as Discontinued Operations	The table below presents the statement of operations data for NSS, which was previously a reportable segment and has been classified as a discontinued operation and includes allocated interest expense for debt not directly attributable or related to L3’s other operations. Interest expense was allocated in accordance with the accounting standards for discontinued operations and was based on the ratio of NSS’s net assets to the sum of: (1) total L3 consolidated net assets and (2) L3 consolidated total debt. First Quarter Ended March 25, 2016 (in millions) Net sales $ 86 Cost of sales (92 ) Gain related to business divestiture 64 Operating income from discontinued operations 58 Interest expense allocated to discontinued operations — Income from discontinued operations before income taxes 58 Income tax benefit 5 Income from discontinued operations, net of income taxes $ 63

Contracts in Process (Tables)

Contracts in Process (Tables)	3 Months Ended
	Mar. 31, 2017
Contracts in Process [Abstract]
Components of Contracts in Process	The components of contracts in process are presented in the table below. March 31, 2017 December 31, 2016 (in millions) Unbilled contract receivables, gross $ 2,116 $ 2,020 Unliquidated progress payments (807 ) (827 ) Unbilled contract receivables, net 1,309 1,193 Inventoried contract costs, gross 1,113 1,065 Unliquidated progress payments (168 ) (203 ) Inventoried contract costs, net 945 862 Total contracts in process $ 2,254 $ 2,055
General and Administrative, Independent Research and Development and Bid and Proposal Costs	The table below presents a summary of G&A, IRAD and B&P costs included in inventoried contract costs and the changes to them, including amounts charged to cost of sales by the Company’s U.S. Government contractor businesses for the periods presented. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Amounts included in inventoried contract costs at beginning of the period $ 173 $ 137 Contract costs incurred: IRAD and B&P 78 65 Other G&A 222 194 Total 300 259 Amounts charged to cost of sales (295 ) (239 ) Amounts included in inventoried contract costs at end of the period $ 178 $ 157
Selling, General and Administrative Expenses and Research and Development Expenses	The table below presents a summary of selling, general and administrative expenses and research and development expenses for the Company’s commercial businesses, which are expensed as incurred and included in cost of sales on the unaudited condensed consolidated statements of operations. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Selling, general and administrative expenses $ 71 $ 52 Research and development expenses 15 11 Total $ 86 $ 63

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2017
Inventories [Abstract]
Inventories at Lower of Cost or Realizable Value	The table below presents the components of inventories at the lower of cost (first-in, first-out or average cost) or realizable value. March 31, 2017 December 31, 2016 (in millions) Raw materials, components and sub-assemblies $ 184 $ 165 Work in process 93 106 Finished goods 76 59 Total $ 353 $ 330

Goodwill and Identifiable Int40

Goodwill and Identifiable Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2017
Goodwill and Identifiable Intangible Assets [Abstract]
Changes in Goodwill by Segment	The table below presents the changes in goodwill allocated to the Company’s reporting units in each reportable segment. Electronic Systems Aerospace Systems Communication Systems Sensor Systems Consolidated Total (in millions) Goodwill (1) $ 2,687 $ 1,698 $ 1,058 $ 1,559 $ 7,002 Accumulated impairment losses (43 ) (338 ) (35 ) (26 ) (442 ) Balance at December 31, 2016 2,644 1,360 1,023 1,533 6,560 Business acquisitions (2) 100 — — 16 116 Business divestitures (3) (12 ) — — — (12 ) Foreign currency translation adjustments (4) 8 2 — 5 15 Balance at March 31, 2017 2,740 1,362 1,023 1,554 6,679 Goodwill 2,783 1,700 1,058 1,580 7,121 Accumulated impairment losses (43 ) (338 ) (35 ) (26 ) (442 ) $ 2,740 $ 1,362 $ 1,023 $ 1,554 $ 6,679 (1) The business realignment in the Electronic Systems segment resulted in a reallocation of goodwill due to changes in reporting units. Goodwill was reallocated to the affected reporting units based upon their relative fair value. The changes to reporting units did not result in a goodwill impairment of any reporting unit. (2) The increase for the Electronic Systems segment was due to the acquisition of the ETD business and the purchase price allocation adjustment for the MacH business acquisition. The increase for the Sensor Systems segment was primarily due to the OceanServer business acquisition. (3) The decrease for the Electronic Systems segment was due to the divestitures of Coleman and Aviation Jet Services during the quarterly period ended March 31, 2017. (4) The increase in the Electronic Systems segment was due to the weakening of the U.S. dollar against the British pound and the Canadian dollar during the quarterly period ended March 31, 2017. The increase in the Aerospace Systems segment was due to the weakening of the U.S. dollar against the Canadian dollar during the quarterly period ended March 31, 2017. The increase in the Sensor Systems segment was due to the weakening of the U.S. dollar against the Australian dollar, the Euro and the British pound during the quarterly period ended March 31, 2017.
Identifiable Intangible Assets	The table below presents information for the Company’s identifiable intangible assets that are subject to amortization. March 31, 2017 December 31, 2016 Weighted Average Amortization Period Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount (in years) (in millions) Customer contractual relationships 15 $ 412 $ 276 $ 136 $ 409 $ 269 $ 140 Technology 10 202 105 97 191 102 89 Other 18 21 12 9 21 12 9 Total 13 $ 635 $ 393 $ 242 $ 621 $ 383 $ 238
Amortization Expense	The table below presents amortization expense recorded by the Company for its identifiable intangible assets. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Amortization expense $ 10 $ 8
Estimated Amortization Expense	Based on gross carrying amounts at March 31, 2017, the Company’s estimate of amortization expense for identifiable intangible assets for the years ending December 31, 2017 through 2021 is presented in the table below. Year Ending December 31, 2017 2018 2019 2020 2021 (in millions) Estimated amortization expense $ 40 $ 38 $ 34 $ 30 $ 27

Other Current Liabilities and41

Other Current Liabilities and Other Liabilities (Tables)	3 Months Ended
	Mar. 31, 2017
Other Current Liabilities and Other Liabilities [Abstract]
Other Current Liabilities	The table below presents the components of other current liabilities. March 31, 2017 December 31, 2016 (in millions) Other Current Liabilities: Accrued product warranty costs $ 80 $ 68 Estimated costs in excess of estimated contract value to complete contracts in process in a loss position 74 70 Accrued interest 48 43 Accruals for pending and threatened litigation (see Note 18) (1) 45 51 Deferred revenues 36 34 Product returns allowance (2) 4 5 Other 157 160 Total other current liabilities $ 444 $ 431 (1) The quarterly period ended March 31, 2017 and the year ended December 31, 2016 included $10 million and $14 million, respectively, in connection with the EoTech matter. (2) On March 23, 2017, the Company ended the voluntary return program for various EoTech HWS products in connection with the preliminary settlement of the class action lawsuit (See Note 18). The product returns allowance, net of refund payments made to eligible owners, was $2 million at March 31, 2017. As of April 16, 2017, the Company had approved refunds at a cost of approximately $36 million, with an average refund cost per unit of $500.
Other Liabilities	The table below presents the components of other liabilities. March 31, 2017 December 31, 2016 (in millions) Other Liabilities: Non-current income taxes payable (see Note 11) $ 123 $ 124 Deferred compensation 50 47 Accrued product warranty costs 36 41 Estimated contingent purchase price payable for acquired businesses (see Note 5) 31 29 Accrued workers’ compensation 29 30 Notes payable and capital lease obligations 14 13 Other 82 84 Total other liabilities $ 365 $ 368
Changes in Company's Accrued Product Warranty Costs	The table below presents the changes in the Company’s accrued product warranty costs. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Accrued product warranty costs: (1) Balance at January 1 $ 109 $ 105 Acquisitions during the period 3 — Accruals for product warranties issued during the period 16 9 Settlements made during the period (12 ) (11 ) Balance at end of period $ 116 $ 103 (1) Warranty obligations incurred in connection with long-term production contracts that are accounted for under the POC cost-to-cost method are included within the contract estimates at completion and are excluded from the above amounts. The balances above include both the current and non-current amounts.

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2017
Debt [Abstract]
Components of Debt and Reconciliation to Carrying Amount of Current and Long-Term Debt	The components of debt and a reconciliation to the carrying amount of long-term debt is presented in the table below. March 31, 2017 December 31, 2016 (in millions) Borrowings under Revolving Credit Facility (1) $ — $ — 5.20% Senior Notes due 2019 1,000 1,000 4.75% Senior Notes due 2020 800 800 4.95% Senior Notes due 2021 650 650 3.95% Senior Notes due 2024 350 350 3.85% Senior Notes due 2026 550 550 Principal amount of long-term debt 3,350 3,350 Unamortized discounts (8 ) (8 ) Deferred debt issue costs (16 ) (17 ) Carrying amount of long-term debt $ 3,326 $ 3,325 (1) During the quarterly period ended March 31, 2017, L3’s aggregate borrowings and repayments under the Credit Facility were $664 million. At March 31, 2017, L3 had the full availability of its $1 billion Credit Facility.

Accumulated Other Comprehensi43

Accumulated Other Comprehensive (Loss) Income (AOCI) (Tables)	3 Months Ended
	Mar. 31, 2017
Accumulated Other Comprehensive (Loss) Income (AOCI) [Abstract]
Summary of AOCI Balances Including Amounts Reclassified from AOCI into Net Income	The changes in the AOCI balances, including amounts reclassified from AOCI into net income, are presented in the table below. Foreign currency translation Unrealized gains (losses) on hedging instruments Unrecognized (losses) gains and prior service cost, net Total accumulated other comprehensive loss (in millions) Balance at December 31, 2016 $ (178 ) $ 6 $ (554 ) $ (726 ) Other comprehensive income before reclassifications, net of tax 19 — — 19 Amounts reclassified from AOCI, net of tax — — 9 9 Net current period other comprehensive income 19 — 9 28 Balance at March 31, 2017 $ (159 ) $ 6 $ (545 ) $ (698 ) Balance at December 31, 2015 $ (101 ) $ (8 ) $ (465 ) $ (574 ) Other comprehensive income before reclassifications, net of tax 1 6 — 7 Amounts reclassified from AOCI, net of tax — 1 8 9 Net current period other comprehensive income 1 7 8 16 Balance at March 25, 2016 $ (100 ) $ (1 ) $ (457 ) $ (558 )
Summary of Amounts Reclassified from AOCI into Net Income	Further details regarding the amounts reclassified from AOCI into net income are presented in the table below. Amount Reclassified from AOCI (a) Affected Line Item in the Unaudited Condensed Consolidated Statements of Operations First Quarter Ended Details About AOCI Components March 31, 2017 March 25, 2016 (in millions) Loss on hedging instruments $ — $ (3 ) Cost of sales-products — (3 ) Income from continuing operations before income taxes — 2 Provision for income taxes $ — $ (1 ) Income from continuing operations Amortization of defined benefit pension items: Net loss $ (15 ) $ (12 ) (b) (15 ) (12 ) Income from continuing operations before income taxes 6 4 Provision for income taxes $ (9 ) $ (8 ) Income from continuing operations Total reclassification for the period $ (9 ) $ (9 ) Income from continuing operations (a) Amounts in parenthesis indicate charges to the unaudited condensed consolidated statements of operations. (b) Amounts related to pension and postretirement benefit plans were reclassified from AOCI and recorded as a component of net periodic benefit cost (see Note 19 for additional information).

L3's Earnings Per Share (Tables

L3's Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2017
L3's Earnings Per Share [Abstract]
Reconciliation of Basic and Diluted Earnings per Share (EPS)	A reconciliation of basic and diluted earnings per share (EPS) is presented in the table below. First Quarter Ended March 31, 2017 March 25, 2016 (in millions, except per share data) Reconciliation of net income: Net income $ 168 $ 230 Net income from continuing operations attributable to noncontrolling interests (4 ) (3 ) Net income attributable to L3’s common shareholders $ 164 $ 227 Earnings attributable to L3’s common shareholders: Continuing operations $ 164 $ 164 Discontinued operations, net of income tax — 63 Net income attributable to L3’s common shareholders $ 164 $ 227 Earnings per share attributable to L3’s common shareholders: Basic: Weighted average common shares outstanding 77.7 77.8 Basic earnings per share: Continuing operations $ 2.11 $ 2.11 Discontinued operations, net of income tax — 0.81 Net income $ 2.11 $ 2.92 Diluted: Common and potential common shares: Weighted average common shares outstanding 77.7 77.8 Assumed exercise of stock options 2.8 2.0 Unvested restricted stock awards 0.8 1.1 Employee stock purchase plan contributions 0.1 0.1 Performance unit awards 0.1 0.1 Assumed purchase of common shares for treasury (2.2 ) (2.1 ) Common and potential common shares 79.3 79.0 Diluted earnings per share: Continuing operations $ 2.07 $ 2.08 Discontinued operations, net of income tax — 0.79 Net income $ 2.07 $ 2.87

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2017
Fair Value Measurements [Abstract]
Company's Assets and Liabilities at Fair Value on Recurring Basis	The following table presents the fair value hierarchy level for each of the Company’s assets and liabilities that are measured and recorded at fair value on a recurring basis. March 31, 2017 December 31, 2016 Description Level 1 (1) Level 2 (2) Level 3 (3) Level 1 (1) Level 2 (2) Level 3 (3) (in millions) Assets Cash equivalents $ 12 $ — $ — $ 104 $ — $ — Derivatives (foreign currency forward contracts) — 11 — — 12 — Total assets $ 12 $ 11 $ — $ 104 $ 12 $ — Liabilities Derivatives (foreign currency forward contracts) $ — $ 3 $ — $ — $ 6 $ — Contingent consideration (4) — — 31 — — 29 Total liabilities $ — $ 3 $ 31 $ — $ 6 $ 29 (1) Level 1 is based on quoted market prices available in active markets for identical assets or liabilities as of the reporting date. Cash equivalents are primarily held in registered money market funds, which are valued using quoted market prices. (2) Level 2 is based on pricing inputs other than quoted prices in active markets, which are either directly or indirectly observable. The fair value is determined using a valuation model based on observable market inputs, including quoted foreign currency forward exchange rates and consideration of non-performance risk. (3) Level 3 is based on pricing inputs that are not observable and not corroborated by market data. (4) The contingent consideration liability represents the future potential earn-out payments relating to the MacH acquisition. The fair value of the contingent consideration liability is based on a Monte Carlo Simulation of the aggregate revenue of MacH for the three-year period ending December 31, 2019. The significant unobservable inputs used in calculating the fair value of the contingent consideration include: (i) projected revenues of the MacH acquired business, (ii) company specific risk premium, which is a component of the discount rate applied to the revenue projections, (iii) and volatility. The fair value of the contingent consideration for potential earn-out payments is reassessed quarterly, including an analysis of the significant inputs used in the evaluation, as well as the accretion of the present value discount. Changes are reflected within cost of sales in the consolidated statements of operations.
Changes to Contingent Consideration Obligations	The table below presents the changes to contingent consideration obligations during the quarterly period ended March 31, 2017. March 31, 2017 (in millions) Balance at beginning of period $ 29 Changes in fair value of contingent consideration, net 2 Balance at end of period $ 31

Financial Instruments (Tables)

Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2017
Financial Instruments [Abstract]
Carrying Amounts and Estimated Fair Values of Company's Long-Term Debt and Foreign Currency Forward Contracts	The carrying amounts and estimated fair values of the Company’s other financial instruments are presented in the table below. March 31, 2017 December 31, 2016 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value (in millions) Senior Notes (1) $ 3,326 $ 3,542 $ 3,325 $ 3,526 Foreign currency forward contracts (2) $ 8 $ 8 $ 6 $ 6 (1) The Company measures the fair value of its Senior Notes using Level 2 inputs based primarily on current market yields for its existing debt traded in the secondary market. (2) The Company measures the fair values of foreign currency forward contracts based on forward exchange rates. See Note 17 for additional disclosures regarding the notional amounts and fair values of foreign currency forward contracts.

Derivative Financial Instrume47

Derivative Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2017
Derivative Financial Instruments [Abstract]
Notional Amounts of Company's Outstanding Foreign Currency Forward Contracts by Currency	The table below presents the notional amounts of the Company’s outstanding foreign currency forward contracts by currency at March 31, 2017. Currency Notional Amounts (in millions) U.S. dollar $ 109 Euro 98 Canadian dollar 73 British pound 35 Other 16 Total $ 331
Location of Company's Derivative Instruments Recorded at Fair Value on the Condensed Consolidated Balance Sheets	The table below presents the location of the Company’s derivative instruments recorded at fair value on the condensed consolidated balance sheets. March 31, 2017 December 31, 2016 Other Current Assets Other Assets Other Current Liabilities Other Liabilities Other Current Assets Other Assets Other Current Liabilities Other Liabilities (in millions) Derivatives designated as hedging instruments: Foreign currency forward contracts (1) $ 9 $ 2 $ 3 $ — $ 10 $ 2 $ 6 $ — Total derivative instruments $ 9 $ 2 $ 3 $ — $ 10 $ 2 $ 6 $ — (1) See Note 15 for a description of the fair value hierarchy related to the Company’s foreign currency forward contracts.

Pension and Other Postretirem48

Pension and Other Postretirement Benefits (Tables)	3 Months Ended
	Mar. 31, 2017
Pension and Other Postretirement Benefits [Abstract]
Components of Net Periodic Benefit Cost	The following table summarizes the components of net periodic benefit cost for the Company’s pension and other postretirement benefit plans. Pension Plans Postretirement Benefit Plans First Quarter Ended First Quarter Ended March 31, 2017 March 25, 2016 March 31, 2017 March 25, 2016 (in millions) Components of net periodic benefit cost: Service cost $ 29 $ 27 $ 1 $ 1 Interest cost 35 35 1 1 Expected return on plan assets (53 ) (51 ) (1 ) (1 ) Amortization of prior service costs (credits) — — — (1 ) Amortization of net loss 16 13 (1 ) — Net periodic benefit cost $ 27 $ 24 $ — $ —

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2017
Stock-Based Compensation [Abstract]
Weighted Average Assumptions in Valuation Model	The weighted average assumptions used in the valuation model for this grant are presented in the table below. Expected holding period (in years) 5.2 Expected volatility 20.1 % Expected dividend yield 2.0 % Risk-free interest rate 2.0 %

Supplemental Cash Flow Inform50

Supplemental Cash Flow Information (Tables)	3 Months Ended
	Mar. 31, 2017
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Interest paid on outstanding debt $ 37 $ 36 Income tax payments $ 20 $ 12 Income tax refunds $ 5 $ 1

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2017
Segment Information [Abstract]
Summary of Segment Information	The tables below present net sales, operating income, depreciation and amortization and total assets by reportable segment. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Net Sales: Aerospace Systems $ 1,045 $ 1,007 Electronic Systems 760 615 Communication Systems 543 477 Sensor Systems 354 290 Elimination of intercompany sales (33 ) (36 ) Consolidated total $ 2,669 $ 2,353 Operating Income: Aerospace Systems $ 69 $ 106 Electronic Systems 91 85 Communication Systems 43 51 Sensor Systems 50 10 Consolidated total $ 253 $ 252 Depreciation and amortization: Aerospace Systems $ 13 $ 13 Electronic Systems 18 14 Communication Systems 12 12 Sensor Systems 11 11 Consolidated total $ 54 $ 50 March 31, 2017 December 31, 2016 (in millions) Total Assets: Electronic Systems $ 4,576 $ 4,369 Aerospace Systems 2,776 2,535 Communication Systems 2,099 2,031 Sensor Systems 2,482 2,433 Corporate 231 497 Consolidated total $ 12,164 $ 11,865

Severance and Restructuring C52

Severance and Restructuring Costs (Tables)	3 Months Ended
	Mar. 31, 2017
Severance and Restructuring Costs [Abstract]
Severance and Restructuring Costs Incurred by Reportable Segment	Severance and restructuring costs incurred by reportable segment are presented in the table below. First Quarter Ended March 31, 2017 March 25, 2016 (in millions) Reportable Segment Electronic Systems $ 3 $ — Aerospace Systems — — Communication Systems 9 1 Sensor Systems 2 1 Consolidated $ 14 $ 2

Condensed Combining Financial53

Condensed Combining Financial Information of L3 and Its Subsidiaries (Tables)	3 Months Ended
	Mar. 31, 2017
Condensed Combining Financial Information of L3 and Its Subsidiaries
Condensed Combining Balance Sheets	The following unaudited condensed combining financial information presents the results of operations, financial position and cash flows of: (1) L3 excluding its consolidated subsidiaries (the Parent), (2) the Guarantor Subsidiaries, (3) the Non-Guarantor Subsidiaries and (4) the eliminations to arrive at the information for L3 on a consolidated basis. As a result of the Merger, prior year amounts have been recast to conform to the current year presentation. L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in miilions) Condensed Combining Balance Sheets: At March 31, 2017: Current assets: Cash and cash equivalents $ 58 $ 1 $ 195 $ (24 ) $ 230 Billed receivables, net 247 353 202 — 802 Contracts in process 733 1,260 261 — 2,254 Other current assets 246 227 113 — 586 Total current assets 1,284 1,841 771 (24 ) 3,872 Goodwill 2,385 3,099 1,195 — 6,679 Other assets 695 611 307 — 1,613 Investment in and amounts due from consolidated subsidiaries 6,074 4,741 — (10,815 ) — Total assets $ 10,438 $ 10,292 $ 2,273 $ (10,839 ) $ 12,164 Current liabilities $ 811 $ 934 $ 508 $ (24 ) $ 2,229 Amounts due to consolidated subsidiaries — — 289 (289 ) — Other long-term liabilities 1,570 204 33 — 1,807 Long-term debt 3,326 — — — 3,326 Total liabilities 5,707 1,138 830 (313 ) 7,362 L3 shareholders’ equity 4,731 9,154 1,443 (10,597 ) 4,731 Noncontrolling interests — — — 71 71 Total equity 4,731 9,154 1,443 (10,526 ) 4,802 Total liabilities and equity $ 10,438 $ 10,292 $ 2,273 $ (10,839 ) $ 12,164 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) At December 31, 2016: Current assets: Cash and cash equivalents $ 291 $ 1 $ 207 $ (136 ) $ 363 Billed receivables, net 261 285 185 — 731 Contracts in process 694 1,125 236 — 2,055 Other current assets 236 187 125 — 548 Total current assets 1,482 1,598 753 (136 ) 3,697 Goodwill 2,380 3,007 1,173 — 6,560 Other assets 705 591 312 — 1,608 Investment in and amounts due from consolidated subsidiaries 5,649 5,650 — (11,299 ) — Total assets $ 10,216 $ 10,846 $ 2,238 $ (11,435 ) $ 11,865 Current liabilities $ 789 $ 1,022 $ 460 $ (136 ) $ 2,135 Amounts due to consolidated subsidiaries — — 284 (284 ) — Other long-term liabilities 1,549 200 32 — 1,781 Long-term debt 3,325 — — — 3,325 Total liabilities 5,663 1,222 776 (420 ) 7,241 L3 shareholders’ equity 4,553 9,624 1,462 (11,086 ) 4,553 Noncontrolling interests — — — 71 71 Total equity 4,553 9,624 1,462 (11,015 ) 4,624 Total liabilities and equity $ 10,216 $ 10,846 $ 2,238 $ (11,435 ) $ 11,865
Condensed Combining Statements of Operations	L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) Condensed Combining Statements of Operations: For the quarter ended March 31, 2017: Total net sales $ 862 $ 1,507 $ 373 $ (73 ) $ 2,669 Total cost of sales (777 ) (1,399 ) (313 ) 73 (2,416 ) Operating income 85 108 60 — 253 Interest expense (42 ) — — — (42 ) Interest and other income, net 3 — 2 — 5 Income from continuing operations before income taxes 46 108 62 — 216 Provision for income taxes (10 ) (24 ) (14 ) — (48 ) Equity in net income of consolidated subsidiaries 128 — — (128 ) — Net income 164 84 48 (128 ) 168 Net income attributable to noncontrolling interests — — — (4 ) (4 ) Net income attributable to L3 $ 164 $ 84 $ 48 $ (132 ) $ 164 Comprehensive income attributable to L3 $ 192 $ 84 $ 68 $ (152 ) $ 192 For the quarter ended March 25, 2016: Total net sales $ 822 $ 1,185 $ 409 $ (63 ) $ 2,353 Total cost of sales (739 ) (1,068 ) (357 ) 63 (2,101 ) Operating income 83 117 52 — 252 Interest expense (41 ) — — — (41 ) Interest and other income, net 3 — 1 — 4 Income from continuing operations before income taxes 45 117 53 — 215 Provision for income taxes (10 ) (26 ) (12 ) — (48 ) Equity in net income of consolidated subsidiaries 192 — — (192 ) — Income from continuing operations 227 91 41 (192 ) 167 Income from discontinued operations, net of income tax — 63 — — 63 Net income 227 154 41 (192 ) 230 Net income attributable to noncontrolling interests — — — (3 ) (3 ) Net income attributable to L3 $ 227 $ 154 $ 41 $ (195 ) $ 227 Comprehensive income attributable to L3 $ 243 $ 162 $ 41 $ (203 ) $ 243
Condensed Combining Statements of Cash Flows	L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) Condensed Combining Statements of Cash Flows For the quarterly period ended March 31, 2017: Operating activities: Net cash from (used in) operating activities from continuing operations $ 144 $ (85 ) 67 $ (41 ) $ 85 Investing activities: Business acquisitions, net of cash acquired (139 ) — — — (139 ) Proceeds from sale of businesses, net of closing date cash balances 15 — 1 — 16 Other investing activities (16 ) (17 ) (3 ) — (36 ) Net cash used in investing activities from continuing operations (140 ) (17 ) (2 ) — (159 ) Financing activities: Dividends paid on L3's common stock (61 ) — — — (61 ) Other financing activities (176 ) 102 (81 ) 153 (2 ) Net cash (used in) from financing activities from continuing operations (237 ) 102 (81 ) 153 (63 ) Effect of foreign currency exchange rate changes on cash — — 4 — 4 Net decrease in cash (233 ) — (12 ) 112 (133 ) Cash and cash equivalents, beginning of the period 291 1 207 (136 ) 363 Cash and cash equivalents, end of the period $ 58 $ 1 $ 195 $ (24 ) $ 230 For the quarterly period ended March 25, 2016: Operating activities: Net cash from (used in) operating activities from continuing operations $ 46 $ 117 $ (32 ) $ (19 ) $ 112 Investing activities: Business acquisitions, net of cash acquired (27 ) — — — (27 ) Proceeds from sale of businesses, net of closing date cash balance 576 — — — 576 Other investing activities 3 (12 ) (10 ) — (19 ) Net cash from (used in) investing activities from continuing operations 552 (12 ) (10 ) — 530 Financing activities: Common stock repurchased (198 ) — — — (198 ) Dividends paid on L3's common stock (58 ) — — — (58 ) Other financing activities (130 ) (46 ) 66 107 (3 ) Net cash (used in) from financing activities from continuing operations (386 ) (46 ) 66 107 (259 ) Net decrease in cash and cash equivalents of discontinued operations — (56 ) — — (56 ) Net increase in cash 212 3 24 88 327 Cash and cash equivalents, beginning of the period 137 — 165 (95 ) 207 Cash and cash equivalents, end of the period $ 349 $ 3 $ 189 $ (7 ) $ 534

Description of Business (Detail

Description of Business (Details) - Segment	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Description of Business [Abstract]
Number of reportable segments	4	3

Basis of Presentation (Details)

Basis of Presentation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 25, 2016	Dec. 31, 2016
Accounting Estimates [Abstract]
Increase in operating income due to changes in contract estimates	$ 41	$ 56
Percentage of increase in consolidated operating income due to changes in contract estimates	16.00%	22.00%
Increase in operating income due to changes in contract estimates, diluted (in dollars per share)	$ 0.33	$ 0.46
Revenue Recognition [Abstract]
Percentage of net sales accounted for under contract accounting standards			50.00%
Percentage of fixed-price type contracts			41.00%
Percentage of cost-plus type contracts			9.00%
Period of performance for contracts accounted for under the percentage-of-completion method of accounting, minimum	1 year

Accounting Standards Issued a56

Accounting Standards Issued and Not Yet Implemented (Details)	Mar. 31, 2017
Accounting Standards Issued and Not Yet Implemented [Abstract]
Percentage of net sales generated from revenue that use the units-of-delivery method	20.00%

Acquisitions and Divestitures,

Acquisitions and Divestitures, Business Acquisitions (Details) £ in Millions, $ in Millions	Jan. 05, 2017USD ($)	Nov. 22, 2016USD ($)	Nov. 22, 2016GBP (£)	Sep. 30, 2016USD ($)	Jan. 22, 2016USD ($)	Mar. 31, 2017USD ($)	Mar. 25, 2016USD ($)	Mar. 17, 2017USD ($)	Dec. 31, 2016USD ($)	Nov. 22, 2016GBP (£)
Business Acquisition [Line Items]
Fair value of liability, contingent consideration						$ 31			$ 29
Goodwill recognized						6,679			$ 6,560
Net sales						2,669	$ 2,353
Income before income taxes						216	$ 215
OceanServer Technology, Inc. [Member]
Business Acquisition [Line Items]
Goodwill recognized								$ 16
Implant Sciences Corporation [Member]
Business Acquisition [Line Items]
Purchase price of acquisition	$ 118
Goodwill recognized	$ 91
OceanServer and ETD Business [Member]
Business Acquisition [Line Items]
Net sales						19
Income before income taxes						$ 1
MacDonald Humfrey (Automation) Limited [Member]
Business Acquisition [Line Items]
Purchase price of acquisition		$ 327	£ 263
Fair value of liability, contingent consideration		29								£ 23
Goodwill recognized		261								209
Identifiable intangible assets		$ 53								43
Weighted average useful life		10 years	10 years
MacDonald Humfrey (Automation) Limited [Member] | Maximum [Member]
Business Acquisition [Line Items]
Business acquisition contingent consideration		$ 38								30
MacDonald Humfrey (Automation) Limited [Member] | Customer Relationships [Member]
Business Acquisition [Line Items]
Identifiable intangible assets		26								21
MacDonald Humfrey (Automation) Limited [Member] | Technology [Member]
Business Acquisition [Line Items]
Identifiable intangible assets		$ 27								£ 22
Advanced Technical Materials, Inc. [Member]
Business Acquisition [Line Items]
Purchase price of acquisition					$ 27
Goodwill recognized					$ 20
Micreo Limited and Aerosim Technologies Inc [Member]
Business Acquisition [Line Items]
Purchase price of acquisition				$ 86
Goodwill recognized				61
Goodwill deductible for income tax purposes				$ 6

Acquisitions and Divestitures58

Acquisitions and Divestitures, Business Divestitures (Details) £ in Millions, $ in Millions	Mar. 01, 2017USD ($)	Feb. 24, 2017USD ($)	Feb. 23, 2017USD ($)	Mar. 01, 2017GBP (£)
CTC Aviation Jet Services Limited [Member]
Business Acquisition [Line Items]
Sale of business, base sales price | £				£ 1
Gain (loss) related to business divestitures	$ 5
Gain (loss) on sale of business after income taxes	$ 5
L3 Coleman Aerospace [Member]
Business Acquisition [Line Items]
Sale of business, base sales price		$ 15
Gain (loss) related to business divestitures		3
Gain (loss) on sale of business after income taxes		$ 2
Display Product Line [Member]
Business Acquisition [Line Items]
Sale of business, base sales price			$ 7
Gain (loss) related to business divestitures			4
Gain (loss) on sale of business after income taxes			$ 3

Acquisitions and Divestitures59

Acquisitions and Divestitures, Discontinued Operations (Details) - USD ($) $ in Millions	Feb. 01, 2016	Mar. 31, 2017	Mar. 25, 2016
Discontinued Operations [Abstract]
Income from discontinued operations, net of income taxes		$ 0	$ 63
NSS [Member]
Discontinued Operations [Abstract]
Net sales			86
Cost of sales			(92)
Gain related to business divestiture			64
Operating income from discontinued operations			58
Interest expense allocated to discontinued operations			0
Income from discontinued operations before income taxes			58
Income tax benefit			5
Income from discontinued operations, net of income taxes			$ 63
CACI International Inc [Member] | Discontinued Operations, Disposed of by Sale [Member]
Discontinued Operations [Abstract]
Proceeds from sale of discontinued operations	$ 547

Acquisitions and Divestitures60

Acquisitions and Divestitures, Unaudited Pro Forma Statements of Operations Data (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Acquisitions and Divestitures [Abstract]
Pro forma net sales	$ 2,672	$ 2,400
Pro forma income from continuing operations attributable to L3	164	165
Pro forma net income attributable to L3	$ 164	$ 228
Pro forma diluted earnings per share from continuing operations (in dollars per share)	$ 2.07	$ 2.10
Pro forma diluted earnings per share (in dollars per share)	$ 2.07	$ 2.89

Contracts in Process (Details)

Contracts in Process (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016	Dec. 31, 2016
Contracts Receivable [Abstract]
Unbilled contract receivables, gross	$ 2,116		$ 2,020
Unliquidated progress payments	(807)		(827)
Unbilled contract receivables, net	1,309		1,193
Inventoried contract costs, gross	1,113		1,065
Unliquidated progress payments	(168)		(203)
Inventoried contract costs, net	945		862
Total contracts in process	2,254		$ 2,055
Summary of Inventory for Long Term Contracts or Programs [Roll Forward]
Amounts included in inventoried contract costs at beginning of the period	173	$ 137
Contract costs incurred [Abstract]
IRAD and B&P	78	65
Other G&A	222	194
Total	300	259
Amounts charged to cost of sales	(295)	(239)
Amounts included in inventoried contract costs at end of the period	178	157
Operating Expenses [Abstract]
Selling, general and administrative expenses	71	52
Research and development expenses	15	11
Total	$ 86	$ 63

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Inventories [Abstract]
Raw materials, components and sub-assemblies	$ 184	$ 165
Work in process	93	106
Finished goods	76	59
Total	$ 353	$ 330

Goodwill and Identifiable Int63

Goodwill and Identifiable Intangible Assets - Allocated by Reportable Segment (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Goodwill		$ 7,121	$ 7,002	[1]
Accumulated impairment losses		(442)	(442)
Balance		6,560
Business acquisitions	[2]	116
Business divestitures	[3]	(12)
Foreign currency translation adjustments	[4]	15
Balance		6,679
Electronic Systems [Member]
Goodwill [Line Items]
Goodwill		2,783	2,687	[1]
Accumulated impairment losses		(43)	(43)
Balance		2,644
Business acquisitions	[2]	100
Business divestitures	[3]	(12)
Foreign currency translation adjustments	[4]	8
Balance		2,740
Aerospace Systems [Member]
Goodwill [Line Items]
Goodwill		1,700	1,698	[1]
Accumulated impairment losses		(338)	(338)
Balance		1,360
Business acquisitions	[2]	0
Business divestitures	[3]	0
Foreign currency translation adjustments	[4]	2
Balance		1,362
Communication Systems [Member]
Goodwill [Line Items]
Goodwill		1,058	1,058	[1]
Accumulated impairment losses		(35)	(35)
Balance		1,023
Business acquisitions	[2]	0
Business divestitures	[3]	0
Foreign currency translation adjustments	[4]	0
Balance		1,023
Sensor Systems [Member]
Goodwill [Line Items]
Goodwill		1,580	1,559	[1]
Accumulated impairment losses		(26)	$ (26)
Balance		1,533
Business acquisitions	[2]	16
Business divestitures	[3]	0
Foreign currency translation adjustments	[4]	5
Balance		$ 1,554
[1]	The business realignment in the Electronic Systems segment resulted in a reallocation of goodwill due to changes in reporting units. Goodwill was reallocated to the affected reporting units based upon their relative fair value. The changes to reporting units did not result in a goodwill impairment of any reporting unit.
[2]	The increase for the Electronic Systems segment was due to the acquisition of the ETD business and the purchase price allocation adjustment for the MacH business acquisition. The increase for the Sensor Systems segment was primarily due to the OceanServer business acquisition.
[3]	The decrease for the Electronic Systems segment was due to the divestitures of Coleman and Aviation Jet Services during the quarterly period ended March 31, 2017.
[4]	The increase in the Electronic Systems segment was due to the weakening of the U.S. dollar against the British pound and the Canadian dollar during the quarterly period ended March 31, 2017. The increase in the Aerospace Systems segment was due to the weakening of the U.S. dollar against the Canadian dollar during the quarterly period ended March 31, 2017. The increase in the Sensor Systems segment was due to the weakening of the U.S. dollar against the Australian dollar, the Euro and the British pound during the quarterly period ended March 31, 2017.

Goodwill and Identifiable Int64

Goodwill and Identifiable Intangible Assets - Identifiable Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016	Dec. 31, 2016
Finite-Lived Intangible Assets Subject to Amortization [Abstract]
Weighted Average Amortization Period	13 years
Gross Carrying Amount	$ 635		$ 621
Accumulated Amortization	393		383
Net Carrying Amount	242		238
Amortization expense	10	$ 8
Estimated Amortization Expense for Identifiable Intangible Assets
Estimated amortization expense, 2017	40
Estimated amortization expense, 2018	38
Estimated amortization expense, 2019	34
Estimated amortization expense, 2020	30
Estimated amortization expense, 2021	$ 27
Customer Contractual Relationships [Member]
Finite-Lived Intangible Assets Subject to Amortization [Abstract]
Weighted Average Amortization Period	15 years
Gross Carrying Amount	$ 412		409
Accumulated Amortization	276		269
Net Carrying Amount	$ 136		140
Technology [Member]
Finite-Lived Intangible Assets Subject to Amortization [Abstract]
Weighted Average Amortization Period	10 years
Gross Carrying Amount	$ 202		191
Accumulated Amortization	105		102
Net Carrying Amount	$ 97		89
Other [Member]
Finite-Lived Intangible Assets Subject to Amortization [Abstract]
Weighted Average Amortization Period	18 years
Gross Carrying Amount	$ 21		21
Accumulated Amortization	12		12
Net Carrying Amount	$ 9		$ 9

Other Current Liabilities and65

Other Current Liabilities and Other Liabilities (Details) $ in Millions		Apr. 16, 2017USD ($)$ / shares	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Other Current Liabilities [Abstract]
Accrued product warranty costs			$ 80	$ 68
Estimated costs in excess of estimated contract value to complete contracts in process in a loss position			74	70
Accrued interest			48	43
Accruals for pending and threatened litigation (see Note 18)	[1]		45	51
Deferred revenues			36	34
Product returns allowance	[2]		4	5
Other			157	160
Total other current liabilities			444	431
Accruals for pending and threatened litigation	[1]		45	51
Other Liabilities [Abstract]
Non-current income taxes payable (see Note 11)			123	124
Deferred compensation			50	47
Accrued product warranty costs			36	41
Estimated contingent purchase price payable for acquired businesses (see Note 5)			31	29
Accrued workers' compensation			29	30
Notes payable and capital lease obligations			14	13
Other			82	84
Total other liabilities			365	368
Electronic Systems [Member] | EoTech HWS [Member]
Other Current Liabilities [Abstract]
Accruals for pending and threatened litigation (see Note 18)			10	14
Product returns allowance			2
Accruals for pending and threatened litigation			$ 10	$ 14
Electronic Systems [Member] | EoTech HWS [Member] | Subsequent Event [Member]
Other Current Liabilities [Abstract]
Approved refunds cost		$ 36
Average refund cost per unit (in dollars per unit) | $ / shares		500
[1]	The quarterly period ended March 31, 2017 and the year ended December 31, 2016, included $10 million and $14 million, respectively, in connection with the EoTech matter.
[2]	On March 23, 2017, the Company ended the voluntary return program for various EoTech HWS products in connection with the preliminary settlement of the class action lawsuit (See Note 18). The product returns allowance, net of refund payments made to eligible owners, was $2 million at March 31, 2017. As of April 16, 2017, the Company had approved refunds at a cost of approximately $36 million, with an average refund cost per unit of $500.

Other Current Liabilities and66

Other Current Liabilities and Other Liabilities - Changes in Company's Accrued Product Warranty Costs (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 25, 2016
Accrued product warranty costs [Roll Forward]:
Balance at January 1	[1]	$ 109	$ 105
Acquisitions during the period	[1]	3	0
Accruals for product warranties issued during the period	[1]	16	9
Settlements made during the period	[1]	(12)	(11)
Balance at end of period	[1]	$ 116	$ 103
[1]	Warranty obligations incurred in connection with long-term production contracts that are accounted for under the POC cost-to-cost method are included within the contract estimates at completion and are excluded from the above amounts. The balances above include both the current and non-current amounts.

Debt (Details)

Debt (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 25, 2016	Dec. 31, 2016
Long-term debt, current and noncurrent
Repayments under the credit facility		$ 664	$ 217
Proceeds under the credit facility		664	$ 217
L-3 Communications Corporation [Member]
Components of Debt [Abstract]
Borrowings under Revolving Credit Facility	[1]	0		$ 0
Principal amount of long-term debt		3,350		3,350
Unamortized discounts		(8)		(8)
Deferred debt issue costs		(16)		(17)
Carrying amount of long-term debt		3,326		3,325
L-3 Communications Corporation [Member] | Revolving Credit Facility [Member]
Long-term debt, current and noncurrent
Available borrowings under credit facility		1,000
Repayments under the credit facility		664
Proceeds under the credit facility		664
L-3 Communications Corporation [Member] | 5.20% Senior Notes due 2019 [Member]
Components of Debt [Abstract]
Principal amount of long-term debt		$ 1,000		1,000
Long-term debt, current and noncurrent
Interest rate on senior notes		5.20%
Debt instrument maturity period		2,019
L-3 Communications Corporation [Member] | 4.75% Senior Notes due 2020 [Member]
Components of Debt [Abstract]
Principal amount of long-term debt		$ 800		800
Long-term debt, current and noncurrent
Interest rate on senior notes		4.75%
Debt instrument maturity period		2,020
L-3 Communications Corporation [Member] | 4.95% Senior Notes due 2021 [Member]
Components of Debt [Abstract]
Principal amount of long-term debt		$ 650		650
Long-term debt, current and noncurrent
Interest rate on senior notes		4.95%
Debt instrument maturity period		2,021
L-3 Communications Corporation [Member] | 3.95% Senior Notes due 2024 [Member]
Components of Debt [Abstract]
Principal amount of long-term debt		$ 350		350
Long-term debt, current and noncurrent
Interest rate on senior notes		3.95%
Debt instrument maturity period		2,024
L-3 Communications Corporation [Member] | 3.85% Senior Notes due 2026 [Member]
Components of Debt [Abstract]
Principal amount of long-term debt		$ 550		$ 550
Long-term debt, current and noncurrent
Interest rate on senior notes		3.85%
Debt instrument maturity period		2,026
[1]	During the quarterly period ended March 31, 2017, L3's aggregate borrowings and repayments under the Credit Facility were $664 million. At March 31, 2017, L3 had the full availability of its $1 billion Credit Facility.

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016	Dec. 31, 2016
Income Taxes [Abstract]
Effective tax rate	22.20%	22.30%
Anticipated decrease in unrecognized tax benefits over the next 12 months	$ 9
Accrued potential interest included within current and non-current income taxes payable	11		$ 11
Accrued potential interest included within current and non-current income taxes payable, after income taxes	6		7
Potential penalties	$ 8		$ 8

Accumulated Other Comprehensi69

Accumulated Other Comprehensive (Loss) Income (AOCI), Summary of AOCI Balances Including Amounts Reclassified from AOCI into Net Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	$ 4,553
Other comprehensive income before reclassifications, net of tax	19	$ 7
Amounts reclassified from AOCI, net of tax	9	9
Net current period other comprehensive income	28	16
Ending Balance	4,731
Accumulated Other Comprehensive Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(726)	(574)
Ending Balance	(698)	(558)
Foreign Currency Translation [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(178)	(101)
Other comprehensive income before reclassifications, net of tax	19	1
Amounts reclassified from AOCI, net of tax	0	0
Net current period other comprehensive income	19	1
Ending Balance	(159)	(100)
Unrealized Gain (Losses) on Hedging Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	6	(8)
Other comprehensive income before reclassifications, net of tax	0	6
Amounts reclassified from AOCI, net of tax	0	1
Net current period other comprehensive income	0	7
Ending Balance	6	(1)
Unrecognized (Losses) Gains and Prior Service Cost, Net [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(554)	(465)
Other comprehensive income before reclassifications, net of tax	0	0
Amounts reclassified from AOCI, net of tax	9	8
Net current period other comprehensive income	9	8
Ending Balance	$ (545)	$ (457)

Accumulated Other Comprehensi70

Accumulated Other Comprehensive (Loss) Income (AOCI), Summary of Amounts Reclassified from AOCI into Net Income (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 25, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of sales-products		$ (1,426)	$ (1,266)
Income from continuing operations before income taxes		216	215
Provision for income taxes		(48)	(48)
Income from continuing operations		168	167
Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income from continuing operations	[1]	(9)	(9)
Loss on Hedging Instruments [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of sales-products	[1]	0	(3)
Income from continuing operations before income taxes	[1]	0	(3)
Provision for income taxes	[1]	0	2
Income from continuing operations	[1]	0	(1)
Amortization of Defined Benefit Pension Items [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net loss	[1],[2]	(15)	(12)
Income from continuing operations before income taxes	[1]	(15)	(12)
Provision for income taxes	[1]	6	4
Income from continuing operations	[1]	$ (9)	$ (8)
[1]	Amounts in parenthesis indicate charges to the unaudited condensed consolidated statements of operations.
[2]	Amounts related to pension and postretirement benefit plans were reclassified from AOCI and recorded as a component of net periodic benefit cost (see Note 19 for additional information).

Equity (Details)

Equity (Details) - USD ($) $ / shares in Units, $ in Millions	Feb. 13, 2017	Apr. 21, 2017	Mar. 31, 2017	Mar. 25, 2016	Dec. 04, 2014
Class of Stock [Line Items]
Number of common shares repurchased (in shares)			0
Aggregate amount of repurchased shares				$ 198
Cash dividends declared per common share (in dollars per share)	$ 0.75		$ 0.75	$ 0.70
Dividend declared date			Feb. 13, 2017
Dividend paid date			Mar. 15, 2017
Dividend paid, record date			Mar. 1, 2017
Cash dividends			$ 61
Accrued dividends through payment			2
Treasury Stock [Member]
Class of Stock [Line Items]
Aggregate amount of repurchased shares				$ 198
Share Repurchase Program December 4, 2014 [Member]
Class of Stock [Line Items]
Amount of shares authorized to be repurchased					$ 1,500
Remaining authorized amount of share repurchase programs			$ 433
Share Repurchase Program December 4, 2014 [Member] | Treasury Stock [Member] | Subsequent Event [Member]
Class of Stock [Line Items]
Number of common shares repurchased (in shares)		66,462
Average price per share of repurchased shares (in dollars per share)		$ 165.48
Aggregate amount of repurchased shares		$ 11

L3's Earnings Per Share (Detail

L3's Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Reconciliation of net income [Abstract]
Net income	$ 168	$ 230
Net income from continuing operations attributable to noncontrolling interests	(4)	(3)
Net income attributable to L3	164	227
Earnings attributable to L3' s common shareholders [Abstract]
Continuing operations	164	164
Discontinued operations, net of income tax	0	63
Net income attributable to L3' s common shareholders	$ 164	$ 227
Basic [Abstract]
Weighted average common shares outstanding (in shares)	77.7	77.8
Basic earnings per share [Abstract]
Continuing operations (in dollars per share)	$ 2.11	$ 2.11
Discontinued operations, net of income tax (in dollars per share)	0	0.81
Basic earnings per share (in dollars per share)	$ 2.11	$ 2.92
Common and potential common shares [Abstract]
Weighted average common shares outstanding (in shares)	77.7	77.8
Assumed purchase of common shares for treasury (in shares)	(2.2)	(2.1)
Common and potential common shares (in shares)	79.3	79
Diluted earnings per share [Abstract]
Continuing operations (in dollars per share)	$ 2.07	$ 2.08
Discontinued operations, net of income tax (in dollars per share)	0	0.79
Diluted earnings per share (in dollars per share)	$ 2.07	$ 2.87
Shares excluded from computation of diluted earnings per share (in shares)	0.3	1.2
Stock Options [Member]
Common and potential common shares [Abstract]
Common and potential common shares (in shares)	2.8	2
Unvested Restricted Stock Awards [Member]
Common and potential common shares [Abstract]
Common and potential common shares (in shares)	0.8	1.1
Performance Unit Awards [Member]
Common and potential common shares [Abstract]
Common and potential common shares (in shares)	0.1	0.1
Employee Stock Purchase Plan Contributions [Member]
Common and potential common shares [Abstract]
Common and potential common shares (in shares)	0.1	0.1

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Liabilities [Abstract]
Contingent consideration		$ 31	$ 31	$ 29
Contingent Consideration, Liability [Abstract]
Balance at beginning of period		29
Changes in fair value of contingent consideration, net		2
Balance at end of period		31
Recurring [Member] | Level 1 [Member]
Assets [Abstract]
Cash equivalents	[1]		12	104
Derivatives (foreign currency forward contracts)	[1]		0	0
Total assets	[1]		12	104
Liabilities [Abstract]
Derivatives (foreign currency forward contracts)	[1]		0	0
Contingent consideration	[1],[2]	0	0	0
Total liabilities	[1]		0	0
Contingent Consideration, Liability [Abstract]
Balance at beginning of period	[1],[2]	0
Balance at end of period	[1],[2]	0
Recurring [Member] | Level 2 [Member]
Assets [Abstract]
Cash equivalents	[3]		0	0
Derivatives (foreign currency forward contracts)	[3]		11	12
Total assets	[3]		11	12
Liabilities [Abstract]
Derivatives (foreign currency forward contracts)	[3]		3	6
Contingent consideration	[2],[3]	0	0	0
Total liabilities	[3]		3	6
Contingent Consideration, Liability [Abstract]
Balance at beginning of period	[2],[3]	0
Balance at end of period	[2],[3]	0
Recurring [Member] | Level 3 [Member]
Assets [Abstract]
Cash equivalents	[4]		0	0
Derivatives (foreign currency forward contracts)	[4]		0	0
Total assets	[4]		0	0
Liabilities [Abstract]
Derivatives (foreign currency forward contracts)	[4]		0	0
Contingent consideration	[2],[4]	31	31	29
Total liabilities	[4]		$ 31	$ 29
Contingent Consideration, Liability [Abstract]
Balance at beginning of period	[2],[4]	29
Balance at end of period	[2],[4]	$ 31
[1]	Level 1 is based on quoted market prices available in active markets for identical assets or liabilities as of the reporting date. Cash equivalents are primarily held in registered money market funds, which are valued using quoted market prices..
[2]	The contingent consideration liability represents the future potential earn-out payments relating to the MacH acquisition. The fair value of the contingent consideration liability is based on a Monte Carlo Simulation of the aggregate revenue of MacH for the three-year period ending December 31, 2019. The significant unobservable inputs used in calculating the fair value of the contingent consideration include: (i) projected revenues of the MacH acquired business, (ii) company specific risk premium, which is a component of the discount rate applied to the revenue projections, (iii) and volatility. The fair value of the contingent consideration for potential earn-out payments is reassessed quarterly, including an analysis of the significant inputs used in the evaluation, as well as the accretion of the present value discount. Changes are reflected within cost of sales in the consolidated statements of operations.
[3]	Level 2 is based on pricing inputs other than quoted prices in active markets, which are either directly or indirectly observable. The fair value is determined using a valuation model based on observable market inputs, including quoted foreign currency forward exchange rates and consideration of non-performance risk.
[4]	Level 3 is based on pricing inputs that are not observable and not corroborated by market data.

Financial Instruments (Details)

Financial Instruments (Details) - USD ($) $ in Millions		Mar. 31, 2017	Dec. 31, 2016
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes	[1]	$ 3,326	$ 3,325
Foreign currency forward contracts	[2]	8	6
Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes	[1]	3,542	3,526
Foreign currency forward contracts	[2]	$ 8	$ 6
[1]	The Company measures the fair value of its Senior Notes using Level 2 inputs based primarily on current market yields for its existing debt traded in the secondary market.
[2]	The Company measures the fair values of foreign currency forward contracts based on forward exchange rates. See Note 17 for additional disclosures regarding the notional amounts and fair values of foreign currency forward contracts.

Derivative Financial Instrume75

Derivative Financial Instruments, Outstanding Forward Contracts by Currency (Details) - Foreign Currency Forward Contracts [Member] $ in Millions	Mar. 31, 2017USD ($)
Derivative [Line Items]
Notional amounts of foreign currency forward contracts	$ 331
U.S. Dollar [Member]
Derivative [Line Items]
Notional amounts of foreign currency forward contracts	109
Euro [Member]
Derivative [Line Items]
Notional amounts of foreign currency forward contracts	98
Canadian Dollar [Member]
Derivative [Line Items]
Notional amounts of foreign currency forward contracts	73
British Pound [Member]
Derivative [Line Items]
Notional amounts of foreign currency forward contracts	35
Other [Member]
Derivative [Line Items]
Notional amounts of foreign currency forward contracts	$ 16

Derivative Financial Instrume76

Derivative Financial Instruments, Fair Value on Consolidated Balance Sheet (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 25, 2016	Mar. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Realized pre-tax loss on forward contract		$ (3)
Estimated net amount of existing gains expected to be reclassified into income within the next 12 months			$ 6
Other Current Assets [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, assets			9	$ 10
Other Current Assets [Member] | Foreign Currency Forward Contracts [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, assets	[1]		9	10
Other Assets [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, assets			2	2
Other Assets [Member] | Foreign Currency Forward Contracts [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, assets	[1]		2	2
Other Current Liabilities [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, liabilities			3	6
Other Current Liabilities [Member] | Foreign Currency Forward Contracts [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, liabilities	[1]		3	6
Other Liabilities [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, liabilities			0	0
Other Liabilities [Member] | Foreign Currency Forward Contracts [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, liabilities	[1]		$ 0	$ 0
[1]	See Note 15 for a description of the fair value hierarchy related to the Company's foreign currency forward contracts.

Commitments and Contingencies (

Commitments and Contingencies (Details) € in Millions, $ in Millions	Feb. 15, 2017Complaint	Dec. 20, 2016USD ($)	Jul. 23, 2014EUR (€)	Aug. 31, 2014Complaint	Mar. 31, 2017USD ($)	Dec. 31, 2016Complaint	Dec. 31, 2015Complaint
Contingencies And Commitments [Line Items]
Recoveries from insurance contracts in connection with liabilities amount | $					$ 34.5
EoTech Class Actions [Member]
Contingencies And Commitments [Line Items]
Number of putative class action complaints against entity						5	5
Number of putative class action complaints against entity consolidated	5
Securities Class Action [Member]
Contingencies And Commitments [Line Items]
Number of putative class action complaints against entity and officers				3
Settlement agreement amount | $		$ 34.5
Property Damages [Member] | HVC Alkmaar [Member]
Contingencies And Commitments [Line Items]
Claims for estimated damages | €			€ 11
Business Interruption [Member] | HVC Alkmaar [Member]
Contingencies And Commitments [Line Items]
Claims for estimated damages | €			€ 35

Pension and Other Postretirem78

Pension and Other Postretirement Benefits, Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Pension Plans [Member]
Components of net periodic benefit cost [Abstract]
Service cost	$ 29	$ 27
Interest cost	35	35
Expected return on plan assets	(53)	(51)
Amortization of prior service costs (credits)	0	0
Amortization of net loss	16	13
Net periodic benefit cost	27	24
Postretirement Benefit Plans [Member]
Components of net periodic benefit cost [Abstract]
Service cost	1	1
Interest cost	1	1
Expected return on plan assets	(1)	(1)
Amortization of prior service costs (credits)	0	(1)
Amortization of net loss	(1)	0
Net periodic benefit cost	$ 0	$ 0

Pension and Other Postretirem79

Pension and Other Postretirement Benefits, Contributions (Details) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to defined benefit plans	$ 4
Expected contributions to plans during the remainder of fiscal year	96
Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Contribution to defined benefit plans	2
Expected contributions to plans during the remainder of fiscal year	$ 8

Stock-Based Compensation, Stock

Stock-Based Compensation, Stock Options (Details) - Stock Options [Member]	3 Months Ended
	Mar. 31, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares) | shares	363,939
Weighted average exercise price (in dollars per share)	$ 168.80
Expiration period of stock options granted from date of grant	10 years
Vesting period	3 years
Weighted average grant date fair value of stock options (in dollars per share)	$ 27.18
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected holding period	5 years 2 months 12 days
Expected volatility	20.10%
Expected dividend yield	2.00%
Risk-free interest rate	2.00%

Stock-Based Compensation, Restr

Stock-Based Compensation, Restricted Stock Units (Details) - Restricted Stock Units [Member]	3 Months Ended
	Mar. 31, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted (in shares) | shares	285,787
Weighted average grant date fair value (in dollars per share) | $ / shares	$ 168.80
Vesting period	3 years
Retirement eligibility, employee age	60 years
Service period, minimum	5 years
Retirement eligibility, employee age with no service requirement	65 years
Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year

Stock-Based Compensation, Perfo

Stock-Based Compensation, Performance Units (Details) - Performance Unit Awards [Member]	3 Months Ended
	Mar. 31, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units granted (in shares) | shares	33,883
Weighted average grant date fair value (in dollars per share) | $ / shares	$ 168.80
Length of service after grant date	3 years
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range	0.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range	200.00%

Supplemental Cash Flow Inform83

Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Supplemental Cash Flow Information [Abstract]
Interest paid on outstanding debt	$ 37	$ 36
Income tax payments	20	12
Income tax refunds	$ 5	$ 1

Segment Information (Details)

Segment Information (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017USD ($)Segment	Mar. 25, 2016USD ($)	Dec. 31, 2016USD ($)Segment
Segment Reporting Information [Line Items]
Number of reportable segments | Segment	4		3
Net Sales [Abstract]
Net sales	$ 2,669	$ 2,353
Operating Income [Abstract]
Operating income	253	252
Depreciation and amortization [Abstract]
Depreciation and amortization	54	50
Total Assets [Abstract]
Total Assets	12,164		$ 11,865
Operating Segments [Member] | Aerospace Systems [Member]
Net Sales [Abstract]
Net sales	1,045	1,007
Operating Income [Abstract]
Operating income	69	106
Depreciation and amortization [Abstract]
Depreciation and amortization	13	13
Total Assets [Abstract]
Total Assets	2,776		2,535
Operating Segments [Member] | Electronic Systems [Member]
Net Sales [Abstract]
Net sales	760	615
Operating Income [Abstract]
Operating income	91	85
Depreciation and amortization [Abstract]
Depreciation and amortization	18	14
Total Assets [Abstract]
Total Assets	4,576		4,369
Operating Segments [Member] | Communication Systems [Member]
Net Sales [Abstract]
Net sales	543	477
Operating Income [Abstract]
Operating income	43	51
Depreciation and amortization [Abstract]
Depreciation and amortization	12	12
Total Assets [Abstract]
Total Assets	2,099		2,031
Operating Segments [Member] | Sensor Systems [Member]
Net Sales [Abstract]
Net sales	354	290
Operating Income [Abstract]
Operating income	50	10
Depreciation and amortization [Abstract]
Depreciation and amortization	11	11
Total Assets [Abstract]
Total Assets	2,482		2,433
Corporate [Member]
Total Assets [Abstract]
Total Assets	231		$ 497
Elimination of Intercompany Sales [Member]
Net Sales [Abstract]
Net sales	$ (33)	$ (36)

Severance and Restructuring C85

Severance and Restructuring Costs (Details) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2017USD ($)Employees	Mar. 25, 2016USD ($)	Dec. 31, 2016USD ($)Employees
Restructuring Cost and Reserve [Line Items]
Number of employees of restructuring costs | Employees	200		700
Remaining balance of employee severance and restructuring costs	$ 19		$ 9
Severance and restructuring costs	14	$ 2	$ 17
Electronic Systems [Member]
Restructuring Cost and Reserve [Line Items]
Severance and restructuring costs	3	0
Aerospace Systems [Member]
Restructuring Cost and Reserve [Line Items]
Severance and restructuring costs	0	0
Communication Systems [Member]
Restructuring Cost and Reserve [Line Items]
Severance and restructuring costs	9	1
Sensor Systems [Member]
Restructuring Cost and Reserve [Line Items]
Severance and restructuring costs	$ 2	$ 1

Condensed Combining Financial86

Condensed Combining Financial Information of L3 and Its Subsidiaries- Condensed Combining Balance Sheets (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016	Mar. 25, 2016	Dec. 31, 2015
Current assets [Abstract]
Cash and cash equivalents	$ 230	$ 363	$ 534	$ 207
Billed receivables, net	802	731
Contracts in process	2,254	2,055
Other current assets	586	548
Total current assets	3,872	3,697
Goodwill	6,679	6,560
Other assets	1,613	1,608
Investment in and amounts due from consolidated subsidiaries	0	0
Total assets	12,164	11,865
Current liabilities	2,229	2,135
Amounts due to consolidated subsidiaries	0	0
Other long-term liabilities	1,807	1,781
Long-term debt	3,326	3,325
Total liabilities	7,362	7,241
L3 shareholders' equity	4,731	4,553
Noncontrolling interests	71	71
Total equity	4,802	4,624	4,451	4,429
Total liabilities and equity	12,164	11,865
L-3 [Member]
Current assets [Abstract]
Cash and cash equivalents	58	291	349	137
Billed receivables, net	247	261
Contracts in process	733	694
Other current assets	246	236
Total current assets	1,284	1,482
Goodwill	2,385	2,380
Other assets	695	705
Investment in and amounts due from consolidated subsidiaries	6,074	5,649
Total assets	10,438	10,216
Current liabilities	811	789
Amounts due to consolidated subsidiaries	0	0
Other long-term liabilities	1,570	1,549
Long-term debt	3,326	3,325
Total liabilities	5,707	5,663
L3 shareholders' equity	4,731	4,553
Noncontrolling interests	0	0
Total equity	4,731	4,553
Total liabilities and equity	10,438	10,216
Guarantor Subsidiaries [Member]
Current assets [Abstract]
Cash and cash equivalents	1	1	3	0
Billed receivables, net	353	285
Contracts in process	1,260	1,125
Other current assets	227	187
Total current assets	1,841	1,598
Goodwill	3,099	3,007
Other assets	611	591
Investment in and amounts due from consolidated subsidiaries	4,741	5,650
Total assets	10,292	10,846
Current liabilities	934	1,022
Amounts due to consolidated subsidiaries	0	0
Other long-term liabilities	204	200
Long-term debt	0	0
Total liabilities	1,138	1,222
L3 shareholders' equity	9,154	9,624
Noncontrolling interests	0	0
Total equity	9,154	9,624
Total liabilities and equity	10,292	10,846
Non-Guarantor Subsidiaries [Member]
Current assets [Abstract]
Cash and cash equivalents	195	207	189	165
Billed receivables, net	202	185
Contracts in process	261	236
Other current assets	113	125
Total current assets	771	753
Goodwill	1,195	1,173
Other assets	307	312
Investment in and amounts due from consolidated subsidiaries	0	0
Total assets	2,273	2,238
Current liabilities	508	460
Amounts due to consolidated subsidiaries	289	284
Other long-term liabilities	33	32
Long-term debt	0	0
Total liabilities	830	776
L3 shareholders' equity	1,443	1,462
Noncontrolling interests	0	0
Total equity	1,443	1,462
Total liabilities and equity	2,273	2,238
Eliminations [Member]
Current assets [Abstract]
Cash and cash equivalents	(24)	(136)	$ (7)	$ (95)
Billed receivables, net	0	0
Contracts in process	0	0
Other current assets	0	0
Total current assets	(24)	(136)
Goodwill	0	0
Other assets	0	0
Investment in and amounts due from consolidated subsidiaries	(10,815)	(11,299)
Total assets	(10,839)	(11,435)
Current liabilities	(24)	(136)
Amounts due to consolidated subsidiaries	(289)	(284)
Other long-term liabilities	0	0
Long-term debt	0	0
Total liabilities	(313)	(420)
L3 shareholders' equity	(10,597)	(11,086)
Noncontrolling interests	71	71
Total equity	(10,526)	(11,015)
Total liabilities and equity	$ (10,839)	$ (11,435)

Condensed Combining Financial87

Condensed Combining Financial Information of L3 and Its Subsidiaries- Condensed Combining Statements of Operations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Condensed Financial Statements, Captions [Line Items]
Total net sales	$ 2,669	$ 2,353
Total cost of sales	(2,416)	(2,101)
Operating income	253	252
Interest expense	(42)	(41)
Interest and other income, net	5	4
Income from continuing operations before income taxes	216	215
Provision for income taxes	(48)	(48)
Equity in net income of consolidated subsidiaries	0	0
Income from continuing operations	168	167
Income from discontinued operations, net of income taxes	0	63
Net income	168	230
Net income attributable to noncontrolling interests	(4)	(3)
Net income attributable to L3	164	227
Comprehensive income attributable to L3	192	243
L-3 [Member]
Condensed Financial Statements, Captions [Line Items]
Total net sales	862	822
Total cost of sales	(777)	(739)
Operating income	85	83
Interest expense	(42)	(41)
Interest and other income, net	3	3
Income from continuing operations before income taxes	46	45
Provision for income taxes	(10)	(10)
Equity in net income of consolidated subsidiaries	128	192
Income from continuing operations		227
Income from discontinued operations, net of income taxes		0
Net income	164	227
Net income attributable to noncontrolling interests	0	0
Net income attributable to L3	164	227
Comprehensive income attributable to L3	192	243
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total net sales	1,507	1,185
Total cost of sales	(1,399)	(1,068)
Operating income	108	117
Interest expense	0	0
Interest and other income, net	0	0
Income from continuing operations before income taxes	108	117
Provision for income taxes	(24)	(26)
Equity in net income of consolidated subsidiaries	0	0
Income from continuing operations		91
Income from discontinued operations, net of income taxes		63
Net income	84	154
Net income attributable to noncontrolling interests	0	0
Net income attributable to L3	84	154
Comprehensive income attributable to L3	84	162
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total net sales	373	409
Total cost of sales	(313)	(357)
Operating income	60	52
Interest expense	0	0
Interest and other income, net	2	1
Income from continuing operations before income taxes	62	53
Provision for income taxes	(14)	(12)
Equity in net income of consolidated subsidiaries	0	0
Income from continuing operations		41
Income from discontinued operations, net of income taxes		0
Net income	48	41
Net income attributable to noncontrolling interests	0	0
Net income attributable to L3	48	41
Comprehensive income attributable to L3	68	41
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Total net sales	(73)	(63)
Total cost of sales	73	63
Operating income	0	0
Interest expense	0	0
Interest and other income, net	0	0
Income from continuing operations before income taxes	0	0
Provision for income taxes	0	0
Equity in net income of consolidated subsidiaries	(128)	(192)
Income from continuing operations		(192)
Income from discontinued operations, net of income taxes		0
Net income	(128)	(192)
Net income attributable to noncontrolling interests	(4)	(3)
Net income attributable to L3	(132)	(195)
Comprehensive income attributable to L3	$ (152)	$ (203)

Condensed Combining Financial88

Condensed Combining Financial Information of L3 and Its Subsidiaries- Condensed Combining Statements of Cash Flows (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 25, 2016
Operating activities [Abstract]
Net cash from (used in) operating activities from continuing operations	$ 85	$ 112
Investing activities [Abstract]
Business acquisitions, net of cash acquired	(139)	(27)
Proceeds from sale of businesses, net of closing date cash balances	16	576
Other investing activities	(36)	(19)
Net cash (used in) from investing activities from continuing operations	(159)	530
Financing activities [Abstract]
Common stock repurchased	0	(198)
Dividends paid on L3's common stock	(61)	(58)
Other financing activities	(2)	(3)
Net cash used in financing activities from continuing operations	(63)	(259)
Effect of foreign currency exchange rate changes on cash and cash equivalents	4	0
Net decrease in cash and cash equivalents of discontinued operations		(56)
Net decrease in cash	(133)	327
Cash and cash equivalents, beginning of the period	363	207
Cash and cash equivalents, end of the period	230	534
L-3 [Member]
Operating activities [Abstract]
Net cash from (used in) operating activities from continuing operations	144	46
Investing activities [Abstract]
Business acquisitions, net of cash acquired	(139)	(27)
Proceeds from sale of businesses, net of closing date cash balances	15	576
Other investing activities	(16)	3
Net cash (used in) from investing activities from continuing operations	(140)	552
Financing activities [Abstract]
Common stock repurchased		(198)
Dividends paid on L3's common stock	(61)	(58)
Other financing activities	(176)	(130)
Net cash used in financing activities from continuing operations	(237)	(386)
Effect of foreign currency exchange rate changes on cash and cash equivalents	0
Net decrease in cash and cash equivalents of discontinued operations		0
Net decrease in cash	(233)	212
Cash and cash equivalents, beginning of the period	291	137
Cash and cash equivalents, end of the period	58	349
Guarantor Subsidiaries [Member]
Operating activities [Abstract]
Net cash from (used in) operating activities from continuing operations	(85)	117
Investing activities [Abstract]
Business acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses, net of closing date cash balances	0	0
Other investing activities	(17)	(12)
Net cash (used in) from investing activities from continuing operations	(17)	(12)
Financing activities [Abstract]
Common stock repurchased		0
Dividends paid on L3's common stock	0	0
Other financing activities	102	(46)
Net cash used in financing activities from continuing operations	102	(46)
Effect of foreign currency exchange rate changes on cash and cash equivalents	0
Net decrease in cash and cash equivalents of discontinued operations		(56)
Net decrease in cash	0	3
Cash and cash equivalents, beginning of the period	1	0
Cash and cash equivalents, end of the period	1	3
Non-Guarantor Subsidiaries [Member]
Operating activities [Abstract]
Net cash from (used in) operating activities from continuing operations	67	(32)
Investing activities [Abstract]
Business acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses, net of closing date cash balances	1	0
Other investing activities	(3)	(10)
Net cash (used in) from investing activities from continuing operations	(2)	(10)
Financing activities [Abstract]
Common stock repurchased		0
Dividends paid on L3's common stock	0	0
Other financing activities	(81)	66
Net cash used in financing activities from continuing operations	(81)	66
Effect of foreign currency exchange rate changes on cash and cash equivalents	4
Net decrease in cash and cash equivalents of discontinued operations		0
Net decrease in cash	(12)	24
Cash and cash equivalents, beginning of the period	207	165
Cash and cash equivalents, end of the period	195	189
Eliminations [Member]
Operating activities [Abstract]
Net cash from (used in) operating activities from continuing operations	(41)	(19)
Investing activities [Abstract]
Business acquisitions, net of cash acquired	0	0
Proceeds from sale of businesses, net of closing date cash balances	0	0
Other investing activities	0	0
Net cash (used in) from investing activities from continuing operations	0	0
Financing activities [Abstract]
Common stock repurchased		0
Dividends paid on L3's common stock	0	0
Other financing activities	153	107
Net cash used in financing activities from continuing operations	153	107
Effect of foreign currency exchange rate changes on cash and cash equivalents	0
Net decrease in cash and cash equivalents of discontinued operations		0
Net decrease in cash	112	88
Cash and cash equivalents, beginning of the period	(136)	(95)
Cash and cash equivalents, end of the period	$ (24)	$ (7)