L3 10-K 23 Feb 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2016	Feb. 17, 2017	Jun. 24, 2016
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 Public Float			$ 10.8
Entity Common Stock, Shares Outstanding		77,798,844
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 363	$ 207
Billed receivables, net of allowances of $13 in 2016 and $15 in 2015	731	746
Contracts in process	2,055	2,081
Inventories	330	333
Other current assets	218	201
Assets of discontinued operations	0	664
Total current assets	3,697	4,232
Property, plant and equipment, net	1,121	1,097
Goodwill	6,560	6,281
Identifiable intangible assets	238	199
Other assets	249	260
Total assets	11,865	12,069
Current liabilities:
Current portion of long-term debt	0	499
Accounts payable, trade	299	297
Accrued employment costs	516	504
Accrued expenses	375	390
Advance payments and billings in excess of costs incurred	492	562
Income taxes payable	22	13
Other current liabilities	431	394
Liabilities of discontinued operations	0	220
Total current liabilities	2,135	2,879
Pension and postretirement benefits	1,177	1,047
Deferred income taxes	236	219
Other liabilities	368	368
Long-term debt	3,325	3,127
Total liabilities	7,241	7,640
Commitments and contingencies (see Note 18)
Shareholders' equity:
Common stock: $.01 par value; 300,000,000 shares authorized, 77,232,204 shares outstanding at December 31, 2016 and 78,133,763 shares outstanding at December 31, 2015	6,285	6,052
Treasury stock (at cost), 82,385,075 shares at December 31, 2016 and 79,375,063 shares at December 31, 2015	(7,224)	(6,851)
Retained earnings	6,218	5,728
Accumulated other comprehensive loss	(726)	(574)
Total shareholders' equity	4,553	4,355
Noncontrolling interests	71	74
Total equity	4,624	4,429
Total liabilities and equity	$ 11,865	$ 12,069

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Allowances for billed receivables	$ 13	$ 15
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)	77,232,204	78,133,763
Treasury stock at cost (in shares)	82,385,075	79,375,063

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net sales:
Products		$ 6,442	$ 6,589	$ 6,839
Services		4,069	3,877	4,147
Total net sales		10,511	10,466	10,986
Cost of sales:
Products		(5,785)	(6,007)	(6,161)
Services		(3,718)	(3,569)	(3,813)
Total cost of sales		(9,503)	(9,576)	(9,974)
Loss related to business divestitures	[1]	0	(31)	0
Goodwill impairment charges	[2]	0	(384)	0
Operating income		1,008	475	1,012
Interest expense		(169)	(169)	(158)
Interest and other income, net		18	17	18
Debt retirement charges		(7)	(1)	0
Income from continuing operations before income taxes		850	322	872
Provision for income taxes		(189)	(25)	(227)
Income from continuing operations		661	297	645
Income (loss) from discontinued operations, net of income taxes		63	(522)	32
Net income (loss)		724	(225)	677
Net income from continuing operations attributable to noncontrolling interests		(14)	(15)	(13)
Net income (loss) attributable to L3		$ 710	$ (240)	$ 664
Basic earnings (loss) per share attributable to common shareholders:
Continuing operations (in dollars per share)		$ 8.36	$ 3.49	$ 7.40
Discontinued operations (in dollars per share)		0.81	(6.46)	0.38
Basic earnings (loss) per share (in dollars per share)		9.17	(2.97)	7.78
Diluted earnings (loss) per share attributable to common shareholders:
Continuing operations (in dollars per share)		8.21	3.44	7.20
Discontinued operations (in dollars per share)		0.80	(6.37)	0.36
Diluted earnings (loss) per share (in dollars per share)		9.01	(2.93)	7.56
Cash dividends declared per common share (in dollars per share)		$ 2.80	$ 2.60	$ 2.40
Weighted average common shares outstanding:
Basic (in shares)		77.4	80.7	85.4
Diluted (in shares)		78.8	81.9	87.8
[1]	See Note 3 for information regarding the Company's business divestitures.
[2]	Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information.

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net income (loss)		$ 724	$ (225)	$ 677
Other comprehensive income (loss):
Foreign currency translation adjustments		(77)	(120)	(123)
Unrealized gains (losses) on hedging instruments	[1]	14	(3)	(6)
Pension and postretirement benefit plans:
Amortization of net loss and prior service cost previously recognized	[2]	30	43	9
Net (loss) gain arising during the period	[3]	(119)	90	(354)
Net change in pension and postretirement benefit plans		(89)	133	(345)
Total other comprehensive (loss) income		(152)	10	(474)
Comprehensive income (loss)		572	(215)	203
Comprehensive income attributable to noncontrolling interests		(14)	(15)	(13)
Comprehensive income (loss) attributable to L3		$ 558	$ (230)	$ 190
[1]	Net of income taxes of $5 million in 2016, income tax benefits of $2 million in 2015 and $1 million in 2014.
[2]	Net of income taxes of $18 million in 2016, $24 million in 2015 and $6 million in 2014.
[3]	Net of income tax benefit of $69 million in 2016, income taxes of $49 million in 2015 and an income tax benefit of $211 million in 2014. The 2015 amount includes $9 million (net of income taxes of $5 million) for the reclassification of actuarial losses into net income related to the Marine Systems International business divestiture in accordance with Accounting Standards Codification 715, Defined Benefit Plans - Pension.

CONSOLIDATED STATEMENTS OF COM6

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Income tax expense (benefit) on unrealized gains (losses) on hedging instruments	$ (5)	$ (2)	$ (1)
Income tax (expense) on amortization of net loss and prior service cost previously recognized	(18)	(24)	(6)
Income tax expense (benefit) on net (loss) gain arising during the period	$ 69	49	$ (211)
Amount includes in other comprehensive income (loss), net actuarial gain (loss), before tax		9
Other comprehensive income (loss), net actuarial gain (loss), tax		$ 5

CONSOLIDATED STATEMENTS OF EQUI

CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Millions, $ 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, 2013	$ 1	$ 5,652	$ (5,288)	$ 5,726	$ (110)	$ 75	$ 6,056
Beginning Balance (in shares) at Dec. 31, 2013	85.8
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income				664		13	677
Other comprehensive income (loss)					(474)		(474)
Distributions to noncontrolling interests						(13)	(13)
Cash dividends declared				(209)			(209)
Shares issued:
Employee savings plans		130					130
Employee savings plans (in shares)	1.2
Exercise of stock options		109					109
Exercise of stock options (in shares)	1.2
Employee stock purchase plan		35					35
Employee stock purchase plan (in shares)	0.3
Vesting of restricted stock and performance units (in shares)	0.6
Repurchases of common stock to satisfy tax withholding obligations		(27)					(27)
Repurchases of common stock to satisfy tax withholding obligations (in shares)	(0.2)
Stock-based compensation expense		52					52
Treasury stock purchased			(823)				(823)
Treasury stock purchased (in shares)	(6.9)
Retirement of Convertible Contingent Debt Securities		(161)					(161)
Other		8					8
Ending Balance at Dec. 31, 2014	$ 1	5,798	(6,111)	6,181	(584)	75	5,360
Ending Balance (in shares) at Dec. 31, 2014	82
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income				(240)		15	(225)
Other comprehensive income (loss)					10		10
Distributions to noncontrolling interests						(16)	(16)
Cash dividends declared				(213)			(213)
Shares issued:
Employee savings plans		120					120
Employee savings plans (in shares)	1.1
Exercise of stock options		74					74
Exercise of stock options (in shares)	0.7
Employee stock purchase plan		34					34
Employee stock purchase plan (in shares)	0.3
Vesting of restricted stock and performance units (in shares)	0.7
Repurchases of common stock to satisfy tax withholding obligations		(33)					(33)
Repurchases of common stock to satisfy tax withholding obligations (in shares)	(0.3)
Stock-based compensation expense		49					49
Treasury stock purchased			(740)				(740)
Treasury stock purchased (in shares)	(6.4)
Other		9					9
Ending Balance at Dec. 31, 2015	$ 1	6,051	(6,851)	5,728	(574)	74	4,429
Ending Balance (in shares) at Dec. 31, 2015	78.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income				710		14	724
Other comprehensive income (loss)					(152)		(152)
Distributions to noncontrolling interests						(17)	(17)
Cash dividends declared				(220)			(220)
Shares issued:
Employee savings plans		115					115
Employee savings plans (in shares)	0.9
Exercise of stock options		53					53
Exercise of stock options (in shares)	0.6
Employee stock purchase plan		31					31
Employee stock purchase plan (in shares)	0.4
Vesting of restricted stock and performance units (in shares)	0.5
Repurchases of common stock to satisfy tax withholding obligations		(21)					(21)
Repurchases of common stock to satisfy tax withholding obligations (in shares)	(0.3)
Stock-based compensation expense		49					49
Treasury stock purchased			(373)				(373)
Treasury stock purchased (in shares)	(3)
Other		6					6
Ending Balance at Dec. 31, 2016	$ 1	$ 6,284	$ (7,224)	$ 6,218	$ (726)	$ 71	$ 4,624
Ending Balance (in shares) at Dec. 31, 2016	77.2

CONSOLIDATED STATEMENTS OF EQU8

CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CONSOLIDATED STATEMENTS OF EQUITY [Abstract]
Cash dividends declared per share (in dollars per share)	$ 2.80	$ 2.60	$ 2.40

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities:
Net income (loss)		$ 724	$ (225)	$ 677
Less: (Income) loss from discontinued operations, net of tax		(63)	522	(32)
Income from continuing operations		661	297	645
Depreciation of property, plant and equipment		162	166	165
Amortization of intangibles and other assets		44	44	49
Deferred income tax provision (benefit)		43	(66)	113
Stock-based employee compensation expense		49	46	50
Contributions to employee savings plans in L3's common stock		113	110	119
Goodwill impairment charges	[1]	0	384	0
Amortization of pension and postretirement benefit plans net loss and prior service cost		48	67	15
Amortization of bond discounts and deferred debt issue costs (included in interest expense)		8	8	7
Loss related to business divestitures	[2]	0	31	0
Other non-cash items		12	(3)	0
Changes in operating assets and liabilities, excluding amounts from acquisitions, divestitures, and discontinued operations:
Billed receivables		30	50	39
Contracts in process		14	32	7
Inventories		22	(38)	0
Other assets		29	(27)	(17)
Accounts payable, trade		4	(32)	(80)
Accrued employment costs		9	34	(5)
Accrued expenses		(17)	14	(14)
Advance payments and billings in excess of costs incurred		(69)	(6)	65
Income taxes		34	(33)	(7)
Other current liabilities		19	(2)	6
Pension and postretirement benefits		(57)	(8)	(44)
All other operating activities		(61)	1	(25)
Net cash from operating activities from continuing operations		1,097	1,069	1,088
Investing activities:
Business acquisitions, net of cash acquired		(388)	(320)	(57)
Proceeds from the sale of businesses, net of closing date cash balances		561	318	1
Capital expenditures		(216)	(197)	(174)
Dispositions of property, plant and equipment		21	3	4
Other investing activities		6	4	5
Net cash used in investing activities from continuing operations		(16)	(192)	(221)
Financing activities:
Proceeds from sale of senior notes		547	0	996
Redemption of CODES		0	0	(935)
Repurchases, redemptions and maturities of senior notes		(856)	(297)	0
Borrowings under revolving credit facility		819	1,194	1,367
Repayments of borrowings under revolving credit facility		(819)	(1,194)	(1,367)
Common stock repurchased		(373)	(740)	(823)
Dividends paid on L3's common stock		(220)	(214)	(208)
Proceeds from exercise of stock options		53	48	93
Proceeds from employee stock purchase plan		31	34	35
Debt issue costs		(10)	0	(8)
Repurchases of common stock to satisfy tax withholding obligations		(21)	(33)	(27)
Other financing activities		(7)	(3)	(16)
Net cash used in financing activities from continuing operations		(856)	(1,205)	(893)
Effect of foreign currency exchange rate changes on cash and cash equivalents		(13)	(19)	(17)
Net cash (used in) from discontinued operations
Operating activities		(56)	56	54
Investing activities		0	(5)	(8)
Net cash (used in) from discontinued operations		(56)	51	46
Change in cash balance in assets held for sale		0	61	(61)
Net increase (decrease) in cash and cash equivalents		156	(235)	(58)
Cash and cash equivalents, beginning of the year		207	442	500
Cash and cash equivalents, end of the year		$ 363	$ 207	$ 442
[1]	Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information.
[2]	See Note 3 for information regarding the Company's business divestitures.

Description of Business

Description of Business	12 Months Ended
	Dec. 31, 2016
Description of Business [Abstract]
Description of Business	1. Description of Business L-3 Communications Holdings, Inc. (L-3 Holdings), a Delaware corporation organized in April 1997, derived all of its operating income and cash flows from its wholly-owned subsidiary, L-3 Communications Corporation (L-3 Corp). On December 31, 2016, the Company completed an internal reorganization to eliminate its holding company structure. Pursuant to the reorganization, L-3 Holdings was merged (the Merger) with and into L-3 Corp, with the subsidiary 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. (the Name Change). As a result of the Merger and the Name Change, all outstanding shares of L-3 Holdings’ common stock were automatically converted into the same number of shares of common stock of L3 Technologies, Inc., with economic, voting and other rights that are substantially identical. The common stock of L3 Technologies, Inc. commenced trading effective January 3, 2017 (the first trading day of 2017) on the New York Stock Exchange under the ticker symbol “LLL”, the same ticker symbol previously used by L-3 Holdings. 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. The Company is the successor of L-3 Communications Holdings, Inc. The Company has the following three reportable segments: (1) Electronic Systems, (2) Aerospace Systems and (3) Communication Systems. Electronic Systems provides a broad range of products and services, including components, products, subsystems, systems, and related services for military and commercial customers in several niche markets across several business areas. These business areas include precision engagement & training, sensor systems, power & propulsion systems, aviation products & security systems, warrior systems and advanced programs. 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. Communication Systems delivers products and services for the global communications market, specializing in strategic and tactical space, airborne, ground and sea-based communication systems. Effective March 1, 2017, the Company will realign its Electronic Systems segment in connection with the retirement of the segment’s president in the second quarter of 2017. The current Electronic Systems segment will be split into two separate segments named (1) Electronic Systems and (2) Sensor Systems. Accordingly, the Company’s structure will consist of the following four segments: (1) Aerospace Systems, (2) Communication Systems, (3) Electronic Systems and (4) Sensor Systems. The Company will report its results under the realigned business segments commencing in the first quarter of 2017 at which time the Company will restate the corresponding information for prior periods. Financial information with respect to each of its segments is included in Note 21. 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

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Summary of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Principles of Consolidation: Accounting Estimates: 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 $148 million, or 15%, of consolidated operating income ($1.22 per diluted share) for the year ended December 31, 2016, increases of $52 million, or 11%, of consolidated operating income ($0.45 per diluted share) for the year ended December 31, 2015, and increases of $72 million, or 7%, of consolidated operating income ($0.52 per diluted share) for the year ended December 31, 2014. Revenue Recognition: 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 contracts with multiple deliverables, the Company applies the separation and allocation guidance under the accounting standard for revenue arrangements with multiple deliverables, unless all the deliverables are covered by contract accounting standards, in which case the Company applies the separation and allocation guidance under contract accounting standards. Revenue arrangements with multiple deliverables are evaluated to determine if the deliverables should be separated into more than one unit of accounting. The Company recognizes revenue for each unit of accounting based on the revenue recognition policies discussed above. Sales and cost of sales in connection with contracts to provide services to the U.S. Government that contain collection risk because the contracts are incrementally funded and subject to the availability of funds appropriated, are deferred until a contract modification is obtained, indicating that adequate funds are available to the contract or task order. Research and Development: Customer-funded research and development costs are incurred pursuant to contracts (revenue arrangements) to perform research and development activities according to customer specifications. These costs are not accounted for as research and development expenses, and are also not indirect contract costs. Instead, these costs are direct contract costs and are expensed to cost of sales when the corresponding revenue is recognized, which is generally as the research and development services are performed. Customer-funded research and development costs are substantially all incurred under cost-plus type contracts with the U.S. Government. Product Warranties: The table below presents the changes in the Company’s accrued product warranty costs. Year Ended December 31, 2016 2015 (in millions) Accrued product warranty costs (1) : Balance at January 1 $ 105 $ 93 Acquisitions during this period 3 1 Accruals for product warranties issued during the period 51 59 Changes to accruals for product warranties existing before January 1 — 2 Foreign currency translation adjustments (1 ) (2 ) Settlements made during the period (49 ) (48 ) Balance at December 31 $ 109 $ 105 (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. Deferred Debt Issue Costs: Pension Plan and Postretirement Benefit Plan Obligations: The Company also provides postretirement medical and life insurance benefits for retired employees and dependents at certain locations. Participants are eligible for these benefits when they retire from active service and meet the eligibility requirements for the Company’s pension plans. These benefits are funded primarily on a pay-as-you-go basis with the retiree generally paying a portion of the cost through contributions, deductibles and coinsurance provisions. In accordance with accounting standards for employee pension and postretirement benefits, the Company recognizes on a plan-by-plan basis the unfunded status of its pension and postretirement benefit plans in the consolidated financial statements and measures its pension and postretirement benefit plan assets and benefit obligations as of December 31. The obligation for the Company’s pension plans and postretirement benefit plans and the related annual costs of employee benefits are calculated based on several long-term assumptions, including discount rates and expected mortality for employee benefit liabilities, and rates of return on plan assets, and expected annual rates for salary increases for employee participants in the case of pension plans, and expected annual increases in the costs of medical and other health care benefits in the case of postretirement benefit obligations. See Note 19, Pensions and Other Employee Benefits Stock-Based Compensation: Compensation expense for restricted stock unit and stock option awards is generally recognized on a straight-line basis over the requisite service period for the entire award based on the grant date fair value. All of the stock options granted to employees by the Company are non-qualified stock options under U.S. income tax regulations. Compensation expense for performance units payable in L3 common stock is based on the fair value of the units at the grant date (measurement date), adjusted each reporting period for progress towards the target award, and recognized on a straight line basis over the requisite service period. Stock-based compensation expense is recognized net of estimated forfeitures. Income Taxes: Income tax accounting standards prescribe: (1) a minimum recognition threshold that an income tax benefit arising from an uncertain income tax position taken, or expected to be taken, on an income tax return is required to meet before being recognized in the financial statements and (2) the measurement of the income tax benefits recognized from such positions. The Company’s accounting policy is to classify uncertain income tax positions that are not expected to be resolved in one year as non-current income tax liabilities and to classify potential interest and penalties on uncertain income tax positions as elements of the provision for income taxes on its financial statements. Cash and Cash Equivalents: Contracts in Process: The Company values its acquired contracts in process in connection with business acquisitions on the date of acquisition at contract value less the Company’s estimated costs to complete the contract and a reasonable profit allowance on the Company’s completion effort. Inventories: Property, Plant and Equipment: Goodwill and Indefinite-lived Intangible Assets: Identifiable Intangible Assets: Derivative Financial Instruments: The Company’s U.S. and foreign businesses enter into contracts with customers, subcontractors or vendors that are denominated in currencies other than their functional currencies. To protect the functional currency equivalent cash flows associated with certain of these contracts, the Company enters into foreign currency forward contracts. The Company’s activities involving foreign currency forward contracts are designed to hedge the changes in the functional currency equivalent cash flows due to movements in foreign exchange rates compared to the functional currency. The foreign currencies hedged are primarily the U.S. dollar, the Euro, the Canadian dollar and the British pound. The Company manages exposure to counterparty non-performance credit risk by entering into foreign currency forward contracts only with major financial institutions that are expected to fully perform under the terms of such contracts. Foreign currency forward contracts are recorded in the Company’s balance sheets at fair value and are generally designated and accounted for as cash flow hedges in accordance with the accounting standards for derivative instruments and hedging activities. Gains and losses on designated foreign currency forward contracts that are highly effective in offsetting the corresponding change in the cash flows of the hedged transactions are recorded net of income taxes in accumulated other comprehensive income (loss) (accumulated OCI) and then recognized in income when the underlying hedged transaction affects income. Gains and losses on foreign currency forward contracts that do not meet hedge accounting criteria are recognized in income immediately. Treasury Stock: Translation of Foreign Currency and Foreign Currency Transactions: Accounting Standards Issued and Not Yet Implemented: , Simplifying the Test for Goodwill Impairment 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 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. New Accounting Standards Implemented: , Improvements to Employee Share-Based Payment Accounting In August 2016, the FASB issued ASU 2016-15 , Statement of Cash Flows — Classification of Certain Cash Receipts and Cash Payments Other accounting standard updates effective for interim and annual periods beginning after December 31, 2016 are not expected to have a material impact on the Company’s financial position, results of operations or cash flows.

Acquisitions and Divestitures

Acquisitions and Divestitures	12 Months Ended
	Dec. 31, 2016
Acquisitions and Divestitures [Abstract]
Acquisitions and Divestitures	3. 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. 2016 Business Acquisitions MacDonald Humfrey (Automation) Limited Acquisition. Micreo Limited and Aerosim Acquisitions. Advanced Technical Materials, Inc. (ATM) Acquisition. Net sales and income before income taxes for L3 MacDonald Humfrey, Micreo, Aerosim and ATM, included in L3’s consolidated statement of operations for the year ended December 31, 2016, are presented in the table below. Year Ended December 31, 2016 (in millions) Net sales $ 37 Income before income taxes $ 7 2015 Business Acquisitions ForceX, Inc. Acquisition. CTC Aviation Group Acquisition. MITEQ, Inc. Acquisition. 2014 Business Acquisition Data Tactics Corporation Acquisition. Business Acquisitions Completed After December 31, 2016 Implant Sciences Acquisition. 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 statements 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. Year Ended December 31, 2016 2015 2014 (in millions) Net sales $ 86 $ 1,088 $ 1,138 Cost of sales (92 ) (1,040 ) (1,065 ) Gain related to business divestiture (1) 64 — — Goodwill impairment charges — (571 ) — Operating income (loss) from discontinued operations 58 (523 ) 73 Interest expense allocated to discontinued operations — (20 ) (20 ) Income (loss) from discontinued operations before income taxes 58 (543 ) 53 Income tax benefit (expense) 5 21 (21 ) Income (loss) from discontinued operations, net of income taxes $ 63 $ (522 ) $ 32 (1) The year ended December 31, 2016 includes a gain of $64 million (before and after income taxes) on the sale of the NSS business. The major classes of assets and liabilities included in discontinued operations related to NSS are presented in the table below. December 31, 2015 (in millions) Assets Current assets $ 201 Property, plant and equipment, net 25 Goodwill (1) 390 Other assets 48 Total assets of discontinued operations $ 664 Liabilities Accounts payable, trade $ 48 Other current liabilities 78 Current liabilities 126 Long-term liabilities 94 Total liabilities of discontinued operations $ 220 (1) The goodwill balance at December 31, 2015 is based on an allocation of the goodwill attributable to the NSS reporting unit to discontinued operations based on the relative fair value of the NSS business retained by L3 and NSS business sold. Business Divestitures 2015 Business Divestitures During the year ended December 31, 2015, the Company completed the sales of Marine Systems International (MSI), Broadcast Sports Inc. (BSI), the Tinsley Product Line and Klein Associates, Inc. (Klein). The adjustments recorded by the Company related to the business divestitures are included in the loss related to business divestitures caption on the audited consolidated statements of operations and discussed below. Additionally, these adjustments, the proceeds received, and net sales included in continuing operations related to the Company’s business divestitures, are summarized in the table below. Year Ended December 31, 2015 Loss Related to Business Divestiture Proceeds Received Net Sales (in millions) MSI divestiture $ (17 ) $ 318 $ 185 BSI divestiture (4 ) 26 7 Tinsley Product Line divestiture (8 ) 4 9 Klein divestiture (2 ) 10 8 Total $ (31 ) $ 358 $ 209 MSI Divestiture. BSI Divestiture. Tinsley Product Line Divestiture. Klein Divestiture. Net sales and income (loss) before income taxes for MSI, BSI, the Tinsley Product Line and Klein, included in L3’s consolidated statements of operations, are presented in the table below on an aggregate basis, and are included in income from continuing operations for all periods presented. Year Ended December 31, 2015 2014 (in millions) Net sales $ 209 $ 596 Income before income taxes $ — $ 27 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 years ended December 31, 2016 and 2015 assuming that the business acquisitions completed during 2016 and 2015 had occurred on January 1, 2015 and January 1, 2014, respectively. The unaudited pro forma Statements of Operations data below includes adjustment for additional amortization expense related to acquired intangible assets, depreciation and estimated reduction to interest income assuming the 2016 and 2015 acquisitions had occurred on January 1, 2015 and January 1, 2014, respectively. Year Ended December 31, 2016 2015 (in millions, except per share data) Pro forma net sales $ 10,655 $ 10,700 Pro forma income from continuing operations attributable to L3 $ 660 $ 307 Pro forma net income (loss) attributable to L3 $ 723 $ (215 ) Pro forma diluted earnings per share from continuing operations $ 8.38 $ 3.74 Pro forma diluted earnings (loss) per share $ 9.18 $ (2.63 ) 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	12 Months Ended
	Dec. 31, 2016
Contracts in Process [Abstract]
Contracts in Process	4. Contracts in Process The components of contracts in process are presented in the table below. The unbilled contract receivables, inventoried contract costs and unliquidated progress payments principally relate to contracts with the U.S. Government and prime contractors or subcontractors of the U.S. Government. In connection with contracts in process assumed by the Company in its business acquisitions, the underlying contractual customer relationships are separately recognized as identifiable intangible assets at the date of acquisition, and are discussed and presented in Note 6. December 31, 2016 2015 (in millions) Unbilled contract receivables, gross $ 2,020 $ 2,120 Unliquidated progress payments (827 ) (892 ) Unbilled contract receivables, net 1,193 1,228 Inventoried contract costs, gross 1,065 975 Unliquidated progress payments (203 ) (122 ) Inventoried contract costs, net 862 853 Total contracts in process $ 2,055 $ 2,081 Unbilled Contract Receivables. Unliquidated Progress Payments. 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. Year Ended December 31, 2016 2015 2014 (in millions) Amounts included in inventoried contract costs at beginning of the year $ 137 $ 114 $ 121 Contract costs incurred: IRAD and B&P 308 284 270 Other G&A 839 822 804 Total 1,147 1,106 1,074 Amounts charged to cost of sales (1,111 ) (1,083 ) (1,081 ) Amounts included in inventoried contract costs at end of the year $ 173 $ 137 $ 114 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 consolidated statements of operations. Year Ended December 31, 2016 2015 2014 (in millions) Selling, general and administrative expenses $ 223 $ 261 $ 297 Research and development expenses 54 52 63 Total $ 277 $ 313 $ 360

Inventories

Inventories	12 Months Ended
	Dec. 31, 2016
Inventories [Abstract]
Inventories	5. Inventories Inventories at Lower of Cost or Market. December 31, 2016 2015 (in millions) Raw materials, components and sub-assemblies $ 165 $ 164 Work in process 106 103 Finished goods 59 66 Total $ 330 $ 333

Goodwill and Identifiable Intan

Goodwill and Identifiable Intangible Assets	12 Months Ended
	Dec. 31, 2016
Goodwill and Identifiable Intangible Assets [Abstract]
Goodwill and Identifiable Intangible Assets	6. Goodwill and Identifiable Intangible Assets Goodwill. Generally, the largest intangible assets from the businesses that the Company acquires are the assembled workforces, which includes the human capital of the management, administrative, marketing and business development, scientific, engineering and technical employees of the acquired businesses. The success of the Company’s businesses, including their ability to retain existing business (revenue arrangements) and to successfully compete for and win new business (revenue arrangements), is primarily dependent on the management, marketing and business development, contracting, engineering and technical skills and knowledge of its employees, rather than on productive capital (plant and equipment, and technology and intellectual property). Additionally, for a significant portion of its businesses, the Company’s ability to attract and retain employees who have U.S. Government security clearances, particularly those of top-secret and above, is critical to its success, and is often a prerequisite for retaining existing revenue arrangements and pursuing new ones. Generally, patents, trademarks and licenses are not material for the Company’s acquired businesses. Furthermore, the Company’s U.S. Government contracts (revenue arrangements) generally permit other companies to use the Company’s patents in most domestic work performed by such other companies for the U.S. Government. Therefore, because intangible assets for assembled workforces are part of goodwill in accordance with the accounting standards for business combinations, the substantial majority of the intangible assets for the Company’s business acquisitions is recognized as goodwill. Additionally, the value assigned to goodwill for the Company’s business acquisitions also includes the value that the Company expects to realize from cost reduction measures that it implements for its acquired businesses. 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 Consolidated Total (in millions) Balance at December 31, 2014 Goodwill $ 3,816 $ 1,730 $ 1,024 $ 6,570 Accumulated impairment losses (43 ) — (15 ) (58 ) 3,773 1,730 1,009 6,512 Business acquisitions (1) 233 — 11 244 Business divestitures (2) (20 ) — — (20 ) Business retained from NSS divestiture 26 — 2 28 Goodwill impairment charges (26 ) (338 ) (20 ) (384 ) Foreign currency translation adjustments (3) (61 ) (39 ) 1 (99 ) Balance at December 31, 2015 Goodwill 3,994 1,691 1,038 6,723 Accumulated impairment losses (4) (69 ) (338 ) (35 ) (442 ) 3,925 1,353 1,003 6,281 Business acquisitions (1) 315 — 20 335 Foreign currency translation adjustments (3) (63 ) 7 — (56 ) Balance at December 31, 2016 Goodwill 4,246 1,698 1,058 7,002 Accumulated impairment losses (69 ) (338 ) (35 ) (442 ) $ 4,177 $ 1,360 $ 1,023 $ 6,560 (1) For the year ended December 31, 2016, the net increase in goodwill for the Electronic Systems segment was due to the L3 MacDonald Humfrey, Aeroism and Micreo business acquisitions, as well as the final purchase price allocations for the L3 ForceX and L3 CTC business acquisitions. The increase in goodwill for the Communication Systems segment was due to the ATM business acquisition. For the year ended December 31, 2015, the net increase in goodwill for the Electronic Systems segment was due to the L3 CTC and L3 ForceX business acquisitions. The increase in goodwill for the Communication Systems segment was due to the Miteq business acquisition. (2) For the year ended December 31, 2015, the decrease in goodwill for the Electronic Systems segment was due to the divestitures of BSI, the Tinsley Product Line and Klein. (3) During 2016, the decrease in goodwill presented in the Electronic Systems segment was due to the strengthening of the U.S. dollar against the British pound, the Euro and the Australian dollar, offset by the weakening of the U.S. dollar against the Canadian dollar. The increase in goodwill presented in the Aerospace Systems segment was due to the weakening of the U.S. dollar against the Canadian dollar. During 2015, the decrease in goodwil presented in the Electronic Systems segment was primarily due to the strengthening of the U.S. dollar against the Canadian dollar, the British pound and the Euro. The decrease in goodwill presented in the Aerospace Systems segment was due to the strengthening of the U.S. dollar against the Canadian dollar. (4) The accumulated impairment losses at December 31, 2015 exclude $571 million of impairment charges recorded during 2015 relating to the NSS reporting unit, which is reported in discontinued operations. As discussed in Note 2, the carrying value of goodwill is tested for impairment annually as of November 30 and on an interim basis, using a two-step process, whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. The Company recorded aggregate goodwill impairment charges of $955 million in 2015 primarily due to a decline in the estimated fair value of the NSS business and the Vertex Aerospace business as a result of the decline in their projected future cash flows. The adjustments the Company recorded related to goodwill impairment charges are presented in a separate caption on the audited consolidated statements of operations and are summarized below. Year Ended December 31, 2015 Goodwill Impairment Charges Continuing Operations Discontinued Operations L3 Consolidated (in millions) Vertex Aerospace reporting unit impairment $ 338 $ — $ 338 NSS reporting unit impairment 37 571 608 Re-allocation of goodwill for business retained from NSS 9 — 9 Total $ 384 $ 571 $ 955 Identifiable Intangible Assets. Information on the Company’s identifiable intangible assets that are subject to amortization is presented in the table below. December 31, 2016 December 31, 2015 Weighed 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 $ 409 $ 269 $ 140 $ 370 $ 246 $ 124 Technology 11 191 102 89 156 91 65 Other 18 21 12 9 21 11 10 Total 14 $ 621 $ 383 $ 238 $ 547 $ 348 $ 199 Amortization expense recorded by the Company for its identifiable intangible assets is presented in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Amortization expense $ 35 $ 35 $ 39 Based on gross carrying amounts at December 31, 2016, 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 million s ) Estimated amortization expense $ 39 $ 35 $ 32 $ 28 $ 24

Other Current Liabilities and O

Other Current Liabilities and Other Liabilities	12 Months Ended
	Dec. 31, 2016
Other Current Liabilities and Other Liabilities [Abstract]
Other Current Liabilities and Other Liabilities	7. Other Current Liabilities and Other Liabilities The table below presents the components of other current liabilities. December 31, 2016 2015 (in millions) Other Current Liabilities: Estimated costs in excess of estimated contract value to complete contracts in process in a loss position $ 70 $ 75 Accrued product warranty costs 68 70 Accruals for pending and threatened litigation (see Note 18) (1) 51 6 Accrued interest 43 45 Deferred revenues 34 32 Product returns allowance (2) 5 20 Other 160 146 Total other current liabilities $ 431 $ 394 (1) The year ended December 31, 2016, includes $14 million accrued in the third quarter of 2016 in connection with the EoTech matter. (2) In November 2015, the Company commenced a voluntary return program and began accepting customer returns for various EoTech HWS products that may have been affected by certain performance issues. The return program gives eligible owners of such HWS products the option to return their products in exchange for a refund of the purchase price, including shipping costs. The Company initially recorded a reduction to net sales of $20 million in the Warrior Systems sector of the Electronic Systems segment in the fourth quarter of 2015 associated with establishing a product returns allowance to reflect the estimated cost of the return program. Beginning in the first quarter of 2016, with the benefit of a larger volume of actual refund transactions, the Company began using a statistical analysis of the voluntary return program to estimate the number and cost of future refunds. In its statistical analysis, the Company utilized empirical models to forecast the expected emergence pattern of new refunds over time to produce a probabilistic distribution of new refund costs that reflects the existing level of estimation uncertainty. Based on this analysis, the Company expects the total cost of the voluntary return program to be approximately $38 million. Accordingly, during 2016 the product returns allowance was increased by $18 million as a reduction to net sales. The product returns allowance, net of refund payments made to eligible owners, was $5 million at December 31, 2016. As of February 3, 2017, the Company had approved refunds at a cost of approximately $35 million, with an average refund cost per unit of $500. The Company will continue to monitor the product returns allowance. The Company’s ongoing evaluation may cause it to record further adjustments to the allowance in future periods. These adjustments could be material. The table below presents the components of other liabilities. December 31, 2016 2015 (in millions) Other Liabilities: Non-current income taxes payable (see Note 16) $ 124 $ 161 Deferred compensation 47 45 Accrued product warranty costs 41 35 Accrued workers’ compensation 30 38 Estimated contingent purchase price payable for acquired businesses (see Note 3) 29 — Notes payable and capital lease obligations 13 10 Other 84 79 Total other liabilities $ 368 $ 368

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	8. Property, Plant and Equipment The table below presents the components of Property, Plant and Equipment. December 31, 2016 2015 (in millions) Land $ 54 $ 60 Buildings and improvements 438 431 Machinery, equipment, furniture and fixtures 1,890 1,736 Leasehold improvements 344 343 Gross property, plant and equipment 2,726 2,570 Accumulated depreciation and amortization (1,605 ) (1,473 ) Property, plant and equipment, net $ 1,121 $ 1,097

Debt

Debt	12 Months Ended
	Dec. 31, 2016
Debt [Abstract]
Debt	9. Debt The components of debt and a reconciliation to the carrying amount of current and long-term debt are presented in the table below. December 31, 2016 2015 (in millions) Borrowings under Revolving Credit Facility (1) $ — $ — 3.95% Senior Notes due 2016 — 500 1.50% Senior Notes due 2017 — 350 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 — Principal amount of long-term debt 3,350 3,650 Unamortized discounts (8 ) (8 ) Deferred debt issue costs (17 ) (16 ) Carrying amount of long-term debt 3,325 3,626 Current portion of long-term debt — (499 ) Carrying amount of long-term debt, excluding current portion $ 3,325 $ 3,127 (1) During 2016, L3's aggregate borrowings and repayments under the Credit Facility were $819 million. L3 had the full availability of its $1 billion Credit Facility at December 31, 2016 and December 31, 2015. L3 Revolving Credit Facility On October 31, 2016, L3 entered into a new five year unsecured revolving credit facility (Credit Facility), which replaced its amended and restated revolving credit agreement dated February 3, 2012. The Credit Facility provides for total aggregate borrowings of $1 billion and any outstanding borrowings under the Credit Facility are due and payable on October 31, 2021. Borrowings under the Credit Facility may consist of: (1) base rate loans, which shall bear interest at a rate equal to the sum of the applicable rate (as defined in the Credit Facility), and the “base rate” (as defined in the Credit Facility) and/or (2) eurodollar loans, which shall bear interest at a rate equal to the sum of the applicable rate plus the “Eurodollar rate” (as defined in the Credit Facility). The applicable rate for base rate loans under the Credit Facility ranges from 0.125% to 1.000%, and the applicable rate for eurodollar loans ranges from 1.125% to 2.000%, in each case based on the long-term debt rating of L3. In addition, the Credit Facility provides for uncommitted incremental revolving facilities and additional term loan facilities in an aggregate principal amount of up to $600 million. L3 Senior Notes The Senior Notes are unsecured senior obligations of L3. The terms of each outstanding Senior Note are presented in the table below. Note Date of Issuance Amount Issued Discount (1) Net Cash Proceeds Effective Interest Rate Redemption at Treasury Rate (2)(3) (in millions) 5.20% Senior Notes due October 2, 2009 $ 1,000 $ 4 $ 987 5.25 % 30 bps 4.75% Senior Notes due May 21, 2010 $ 800 $ 3 $ 790 4.79 % 25 bps 4.95% Senior Notes due February 7, 2011 $ 650 $ 4 $ 639 5.02 % 25 bps 3.95% Senior Notes due May 28, 2014 $ 650 $ 3 $ 641 (4) 4.02 % 20 bps 3.85% Senior Notes due December 5, 2016 $ 550 $ 3 $ 542 3.91 % 25 bps (1) Bond discounts are recorded as a reduction to the principal amount of the notes and are amortized as interest expense over the term of the notes. (2) The Senior Notes maturing in 2019, 2020 and 2021 may be redeemed at any time prior to their maturity and the Senior Notes maturing in 2024 and 2026 may be redeemed at any time prior to February 28, 2024 and September 15, 2026, respectively, (three months prior to their maturity) at the option of L3, in whole or in part, at a redemption price equal to the greater of: (1) 100% of the principal amount, or (2) the present value of the remaining principal and interest payments discounted to the date of redemption, on a semi-annual basis, at the Treasury Rate (as defined in the indentures governing the Senior Notes), plus the spread indicated in the table above. In addition, if the Senior Notes maturing in 2024 and 2026 are redeemed at any time on or after February 28, 2024 and September 15, 2026, respectively, the redemption price would be equal to 100% of the principal amount. (3) Upon the occurrence of a change in control (as defined in the indentures governing the Senior Notes), each holder of the notes will have the right to require L3 to repurchase all or any part of such holder’s notes at an offer price in cash equal to 101% of the aggregate principal amount plus accrued and unpaid interest, if any, to the date of purchase. (4) The net cash proceeds of $988 million (after deduction of the bond discount, underwriting expenses and commissions and other related expenses) were used primarily to fund the CODES retirement as discussed below. The remaining net proceeds were used for general corporate purposes. Issuance of Senior Notes On December 5, 2016, the Company issued $550 million aggregate principal amount of 3.85% Senior Notes that mature on December 15, 2026 (the 2026 Notes). The 2026 Notes were issued at a bond discount of $3 million. The net cash proceeds of $542 million from the offering plus cash on hand were used primarily to: (1) replenish the amount of cash used, and the amount of revolving credit borrowings drawn, to repay $200 million aggregate principal amount of its 3.95% Senior Notes which matured on November 15, 2016 (the 2016 Notes), and (2) redeem all of its outstanding 1.50% Senior Notes due May 28, 2017 (the 2017 Notes), which had an aggregate principal amount of $350 million. Repurchases, Redemptions and Maturities of Senior Notes The repurchases, redemptions and maturities of senior notes are presented in the table below. Note Settlement Type Date Settled Aggregate Amount Debt Retirement Charge Cash Payments (in millions) 1.50% Senior Notes due 2017 (1) Redemption December 30, 2016 $ 350 $ 2 $ 351 3.95% Senior Notes due 2016 Maturity November 15, 2016 $ 200 $ — $ 200 3.95% Senior Notes due 2016 (2) Redemption May 20, 2016 $ 300 $ 5 $ 305 3.95% Senior Notes due 2024 Tender Offer December 22, 2015 $ 300 $ 1 $ 297 CODES due 2035 (3) Redemption June 20, 2014 $ 689 $ — $ 935 (1) The 1.50% Senior Notes due 2017 were redeemed at a price equal to 100.323% of the principal amount thereof , plus accrued and unpaid interest to the redemption date. Interest ceased to accrue on and after the redemption date. (2) The 3.95% Senior Notes due 2016 were redeemed at a price equal to 101.475% of the principal amount thereof, plus accrued and unpaid interest. Interest ceased to accrue on and after May 20, 2016 and the only remaining right of holders of such Notes was to receive payment of the Redemption Price and accrued interest. (3) In 2005, L3 sold $700 million of 3% Convertible Contingent Debt Securities (CODES) due August 1, 2035. On February 2, 2011, L3 reporchased approximately $11 million of the CODES. The conversion value of CODES of $935 million was calculated in accordance with the indenture governing the CODES. L3 settled the entire conversion value with respect to converted CODES in cash. As a result of the conversion, the Company recorded a reduction to shareholders’ equity of $161 million, related to the excess conversion value over the fair value of the debt component of the CODES, net of deferred tax liability. Interest expense recognized for the CODES was $2 million for the year ended December 31, 2014. Guarantees The borrowings under the Credit Facility are fully and unconditionally guaranteed by L3 and by substantially all of the material 100% owned domestic subsidiaries of L3 on an unsecured senior basis. The payment of principal and premium, if any, and interest on the Senior Notes is fully and unconditionally guaranteed, on an unsecured senior basis, jointly and severally, by L3’s material 100% owned domestic subsidiaries that guarantee any of its other indebtedness. Subordination The guarantees of the Credit Facility and the Senior Notes rank pari passu with each other. Covenants Financial and other restrictive covenants. The indentures governing the Senior Notes (Senior Indentures) contain covenants customary for investment grade notes, including covenants that restrict the ability of L3 and its 100% owned domestic subsidiaries to create, incur, assume or permit to exist any lien, except permitted liens (as defined in the Senior Indentures) and restrict the ability of L3 and its subsidiaries to enter into certain sale and leaseback transactions (as defined in the Senior Indentures). Cross default provisions.

Accumulated Other Comprehensive

Accumulated Other Comprehensive (Loss) Income (AOCI)	12 Months Ended
	Dec. 31, 2016
Accumulated Other Comprehensive (Loss) Income (AOCI) [Abstract]
Accumulated Other Comprehensive (Loss) Income (AOCI)	10. 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, 2013 $ 142 $ 1 $ (253 ) $ (110 ) Other comprehensive loss before reclassifications, net of tax (123 ) (13 ) (354 ) (490 ) Amounts reclassified from AOCI, net of tax — 7 9 16 Net current period other comprehensive (loss) (123 ) (6 ) (345 ) (474 ) Balance at December 31, 2014 $ 19 $ (5 ) $ (598 ) $ (584 ) Other comprehensive (loss) income before reclassifications, net of tax (161 ) (15 ) 81 (95 ) Amounts reclassified from AOCI, net of tax 41 12 52 105 Net current period other comprehensive (loss) income (120 ) (3 ) 133 10 Balance at December 31, 2015 $ (101 ) $ (8 ) $ (465 ) $ (574 ) Other comprehensive (loss) income before reclassifications, net of tax (77 ) 3 (119 ) (193 ) Amounts reclassified from AOCI, net of tax — 11 30 41 Net current period other comprehensive (loss) income (77 ) 14 (89 ) (152 ) Balance at December 31, 2016 $ (178 ) $ 6 $ (554 ) $ (726 ) 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 Audited Consolidated Statements of Operations Year Ended December 31, Details About AOCI Components 2016 2015 2014 (in millions) Foreign currency translation adjustments: MSI divestiture $ — $ (41 ) $ — Loss related to business divestitures — (41 ) — Income from continuing operations before income taxes $ — $ (41 ) $ — Income from continuing operations Loss on hedging instruments: MSI divestiture $ — $ (2 ) $ — Loss related to business divestitures Other (13 ) (16 ) (8 ) Cost of sales-products (13 ) (18 ) (8 ) Income from continuing operations before income taxes 2 6 1 Provision for income taxes $ (11 ) $ (12 ) $ (7 ) Income from continuing operations Amortization of defined benefit pension items: MSI divestiture $ — $ (14 ) $ — Loss related to business divestitures Net loss (48 ) (67 ) (15 ) (b) (48 ) (81 ) (15 ) Income from continuing operations before income taxes 18 29 6 Provision for income taxes $ (30 ) $ (52 ) $ (9 ) Income from continuing operations Total reclassification for the period $ (41 ) $ (105 ) $ (16 ) Income from continuing operations (a) Amounts in parentheses indicate charges to the 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	12 Months Ended
	Dec. 31, 2016
Equity [Abstract]
Equity	11. 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. L3 repurchased 3.0 million shares of its common stock at an average price of $123.95 per share for an aggregate amount of $373 million from January 1, 2016 through December 31, 2016. All share repurchases of L3’s common stock have been recorded as treasury shares. At December 31, 2016, the remaining dollar value of authorization under the December 4, 2014 share repurchase program was $433 million. From January 1, 2017 through February 17, 2017, L3 did not repurchase shares of its common stock. On February 13, 2017, L3’s Board of Directors declared a quarterly cash dividend of $0.75 per share, payable on March 15, 2017 to shareholders of record at the close of business on March 1, 2017. During the year ended December 31, 2016, the Company paid $220 million of cash dividends. Payments of previously accrued dividends for employee held stock awards were offset by accrued dividends to be paid in future periods.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	12. 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. December 31, 2016 2015 Description Level 1 (1) Level 2 (2) Level 3 (3) Level 1 (1) Level 2 (2) Level 3 (3) (in millions) Assets Cash equivalents $ 104 $ — $ — $ 187 $ — $ — Derivatives (foreign currency forward contracts) — 12 — — 2 — Total assets $ 104 $ 12 $ — $ 187 $ 2 $ — Liabilities Derivatives (foreign currency forward contracts) $ — $ 6 $ — $ — $ 16 $ — Contingent consideration (4) — — 29 — — — Total liabilities $ — $ 6 $ 29 $ — $ 16 $ — (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 L3 MacDonald Humfrey acquisition. The fair value of the contingent consideration liability is based on a Monte Carlo Simulation of the aggregate revenue of L3 MacDonald Humfrey 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 L3 MacDonald Humfrey 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.

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2016
Financial Instruments [Abstract]
Financial Instruments	13. Financial Instruments At December 31, 2016 and 2015, 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 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. December 31, 2016 December 31, 2015 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value (in millions) Senior Notes (1) $ 3,325 $ 3,526 $ 3,626 $ 3,754 Foreign currency forward contracts (2) $ 6 $ 6 $ (14 ) $ (14 ) (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 14 for additional disclosures regarding the notional amounts and fair values of foreign currency forward contracts.

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2016
Derivative Financial Instruments [Abstract]
Derivative Financial Instruments	14. Derivative Financial Instruments Notional amounts are used to measure the volume of foreign currency forward contracts and do not represent exposure to foreign currency losses. The table below presents the notional amounts of the Company’s outstanding foreign currency forward contracts by currency at December 31, 2016. Currency Notional Amount (in millions) U.S. dollar $ 117 Euro 109 Canadian dollar 96 British pound 28 Other 8 Total $ 358 At December 31, 2016, 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 consolidated balance sheets. December 31, 2016 December 31, 2015 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) $ 10 $ 2 $ 6 $ — $ 1 $ 1 $ 15 $ 1 Total derivative instruments $ 10 $ 2 $ 6 $ — $ 1 $ 1 $ 15 $ 1 (1) See Note 12 for a description of the fair value hierarchy related to the Company's foreign currency forward contracts. The effects from foreign currency forward contracts on the consolidated statements of operations were a pre-tax loss of $13 million for the year ended December 31, 2016, a pre-tax loss of $18 million for the year ended December 31, 2015, and a pre-tax loss of $8 million for the year ended December 31, 2014. At December 31, 2016, the estimated net amount of existing gains that are expected to be reclassified into income within the next 12 months is $5 million.

L3's Earnings Per Share

L3's Earnings Per Share	12 Months Ended
	Dec. 31, 2016
L3's Earnings Per Share [Abstract]
L3's Earnings Per Share	15. L3’s Earnings Per Share A reconciliation of basic and diluted earnings per share (EPS) is presented in the table below. Year Ended December 31, 2016 2015 2014 (in millions, except per share data) Reconciliation of net income (loss): Net income (loss) $ 724 $ (225 ) $ 677 Net income from continuing operations attributable to noncontrolling interests (14 ) (15 ) (13 ) Net income (loss) attributable to L3’s common shareholders $ 710 $ (240 ) $ 664 Earnings (loss) attributable to L3’s common shareholders: Continuing operations $ 647 $ 282 $ 632 Discontinued operations, net of income tax 63 (522 ) 32 Net income (loss) attributable to L3’s common shareholders $ 710 $ (240 ) $ 664 Earnings (loss) per share attributable to L3’s common shareholders: Basic: Weighted average common shares outstanding 77.4 80.7 85.4 Basic earnings (loss) per share: Continuing operations $ 8.36 $ 3.49 $ 7.40 Discontinued operations, net of income tax 0.81 (6.46 ) 0.38 Net income (loss) $ 9.17 $ (2.97 ) $ 7.78 Diluted: Common and potential common shares: Weighted average common shares outstanding 77.4 80.7 85.4 Assumed exercise of stock options 2.6 2.4 3.0 Unvested restricted stock awards 1.0 1.3 1.6 Employee stock purchase plan contributions 0.1 0.1 — Performance unit awards 0.1 0.1 0.1 Assumed purchase of common shares for treasury (2.4 ) (2.7 ) (3.1 ) Assumed conversion of the CODES (1) — — 0.8 Common and potential common shares 78.8 81.9 87.8 Diluted earnings (loss) per share: Continuing operations $ 8.21 $ 3.44 $ 7.20 Discontinued operations, net of income tax 0.80 (6.37 ) 0.36 Net income (loss) $ 9.01 $ (2.93 ) $ 7.56 (1) The CODES were retired on June 20, 2014 and were dilutive for the year ended December 31, 2014 as the average market price of L3’s common stock during the period that the CODES were outstanding was greater than the price at which the CODES would have been convertible into L3’s common stock. As of June 18, 2014, the final date of conversion, the conversion price was $88.71. The computation of diluted EPS excluded shares for stock options and employee stock purchase plan contributions of 0.4 million, 0.6 million and 0.5 million for the years ended December 31, 2016, 2015 and 2014, respectively, as they were anti-dilutive.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Taxes [Abstract]
Income Taxes	16. Income Taxes Income from continuing operations before income taxes is summarized in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Domestic $ 654 $ 192 $ 707 Foreign 196 130 165 Income from continuing operations before income taxes $ 850 $ 322 $ 872 The components of the Company’s current and deferred portions of the provision for income taxes on continuing operations are presented in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Current income tax provision: Federal $ 88 $ 60 $ 78 State and local 10 5 1 Foreign 48 26 35 Subtotal 146 91 114 Deferred income tax provision/(benefit): Federal 37 (67 ) 101 State and local 6 (1 ) 11 Foreign — 2 1 Subtotal 43 (66 ) 113 Total provision for income taxes $ 189 $ 25 $ 227 A reconciliation of the statutory federal income tax rate to the effective income tax rate on continuing operations of the Company is presented in the table below. Year Ended December 31, 2016 2015 2014 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % State and local income taxes, net of federal income tax benefit 2.3 2.0 2.1 Foreign income taxes (2.9 ) (14.2 ) (3.6 ) Manufacturing benefits (2.2 ) (3.7 ) (1.7 ) Research and experimentation and other tax credits (4.4 ) (12.9 ) (4.3 ) Resolution of tax contingencies (2.9 ) (2.8 ) (1.0 ) Tax deductible dividends (0.9 ) (2.3 ) (0.8 ) Equity compensation - excess income tax benefits (2.0 ) — — Goodwill impairment — 6.6 — Other, net 0.2 0.1 0.3 Effective income tax rate on continuing operations 22.2 % 7.8 % (1) 26.0 % (1) In 2015, the Company recorded non-cash goodwill impairment charges of $384 million, which resulted in a deferred tax benefit of $120 million. Excluding the goodwill impairment charge and the related deferred income tax benefit, the effective income tax rate for 2015 would have been 20.5%. The significant components of the Company’s net deferred tax assets and liabilities are presented in the table below. December 31, 2016 2015 (in millions) Deferred tax assets: Inventoried costs $ 63 $ 56 Compensation and benefits 152 147 Pension and postretirement benefits 415 354 Loss carryforwards 18 12 Tax credit carryforwards 6 6 Other 89 79 Deferred tax assets 743 654 Less: valuation allowance (12 ) (9 ) Deferred tax assets, net of valuation allowance 731 645 Deferred tax liabilities: Goodwill and other intangible assets $ (752 ) $ (675 ) Income recognition on contracts in process (63 ) (36 ) Property, plant and equipment (96 ) (94 ) Other (54 ) (56 ) Deferred tax liabilities (965 ) (861 ) Total deferred tax liabilities, net of valuation allowance $ (234 ) $ (216 ) The classification of the Company’s deferred tax assets and liabilities are presented in the table below. December 31, 2016 2015 (in millions) Non-current deferred tax assets $ 2 $ 3 Non-current deferred tax liabilities (236 ) (219 ) Total net deferred tax liabilities $ (234 ) $ (216 ) Non-current deferred tax assets are presented in other assets on the consolidated balance sheets. The following table presents the Company’s loss and tax credit carryforwards at December 31, 2016 on a tax return basis. The Company has established a valuation allowance as indicated in those instances in which it does not believe that it is more likely than not it will generate sufficient taxable income, of the appropriate character and in the applicable subsidiary, to utilize the carryforwards. Year Ended December 31, 2016 Carryforwards Valuation Allowances Gross Tax Effected Gross Tax Effected Expiration Periods (in millions) (in millions) Capital loss carryforwards $ 6 $ 2 $ 6 $ 2 2017-2021 Federal net operating loss carryforwards 33 11 5 2 2026-2035 Foreign net operating loss carryforwards 14 3 3 1 Indefinite State net operating loss carryforwards 136 2 47 1 2017-2036 Total loss carryforwards $ 18 $ 6 State tax credit carryforwards 7 5 7 4 2017-2031 Foreign tax credit carryforwards 1 1 — — Indefinite Total tax credit carryforwards $ 6 $ 4 At December 31, 2016, the total amount of unrecognized tax benefits was $111 million, $92 million of which would reduce the effective income tax rate, if recognized. A reconciliation of the change in unrecognized income tax benefits, excluding potential interest and penalties, is presented in the table below. 2016 2015 2014 (in millions) Balance at January 1 $ 140 $ 169 $ 155 Additions for tax positions related to the current year 16 14 20 Additions for tax positions related to prior years 2 2 12 Reductions for tax positions related to prior years (39 ) (37 ) (11 ) Reductions for tax positions related to settlements with taxing authorities (1 ) (1 ) (1 ) Reduction for tax positions related to prior years as a result of a lapse of statute of limitations (7 ) (7 ) (6 ) Balance at December 31 $ 111 $ 140 $ 169 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 December 31, 2016, the statutes of limitations for the Company’s U.S. Federal income tax returns for the years ended December 31, 2010 through 2015 are 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 through 2014. The Company cannot predict the outcome of the audits at this time. At December 31, 2016, 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. During the years ended December 31, 2016, 2015 and 2014, the Company effectively settled various Federal, state and local and foreign audits. As a result of these settlements, the Company reversed previously accrued income tax expense of $25 million, $9 million and $8 million, including potential interest and penalties. At December 31, 2016 and 2015, current and non-current income taxes payable include accrued potential interest of $11 million ($7 million after income taxes) and $18 million ($11 million after income taxes), respectively, and potential penalties of $8 million and $9 million, respectively. With respect to the interest related items, the Company’s income tax expense included a benefit of $4 million for the year ended December 31, 2016 and an expense of $2 million for the year ended December 31, 2015. Prior to 2015, the Company recorded a deferred tax liability related to the repatriation of earnings from certain subsidiaries. During 2015, the Company completed a legal restructuring of its significant foreign operations, and the earnings of these subsidiaries are now considered reinvested indefinitely. As a result, the Company recognized a $17 million deferred tax benefit in the year ended December 31, 2015. At December 31, 2016, the Company had not provided deferred U.S. income taxes and foreign withholding taxes for $708 million of undistributed earnings by its non-U.S. subsidiaries as such earnings are intended to be reinvested indefinitely. Quantification of additional taxes that may be payable on distribution is not practicable.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2016
Stock-Based Compensation [Abstract]
Stock-Based Compensation	17. Stock-Based Compensation Stock-Based Compensation Plans. On May 3, 2016, the stockholders of L3 approved an amendment to its 2008 LTPP to increase the number of shares authorized for issuance by 6.8 million shares to approximately 26.0 million shares. Each share of L3’s common stock issued under a full value award (that is, awards other than stock options and stock appreciation rights) granted on or after February 23, 2016 is counted as 4.26 shares for purposes of this share limit. Each share issued under full value awards granted between February 26, 2013 and February 22, 2016 is counted as 3.69 shares for purposes of the share limit. At December 31, 2016, 9.2 million shares of L3’s common stock remained available for future awards under the 2008 LTPP. The Company’s stock-based compensation by form of award, including stock-based compensation recorded in discontinued operations relating to the NSS business, is presented in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Stock options $ 10 $ 9 $ 9 Restricted stock units 35 38 40 Performance units 4 2 3 Total before income taxes 49 49 52 Income taxes (18 ) (18 ) (20 ) Total after income taxes 31 31 32 Less: Stock-based compensation recorded in discontinued operations, net of income taxes 1 (1) 1 1 Stock-based compensation recorded in continuing operations, net of income taxes $ 30 $ 30 $ 31 (1) Amount relates to the net impact of share based payment award modification in connection with the sale of NSS, which is further discussed below. Stock Options. Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (in thousands) (in years) (in millions) Number of shares under option: Outstanding at January 1, 2016 2,931.5 $ 92.59 6.0 $ 84 Options granted 617.6 116.68 Options exercised (647.5 ) 82.78 Options forfeited (54.1 ) 118.82 Outstanding at December 31, 2016 2,847.5 $ 99.54 6.1 $ 150 Vested and expected to vest at December 31, 2016 (1) 2,835.7 $ 99.46 6.1 $ 149 Exercisable at December 31, 2016 1,802.0 $ 87.77 4.9 $ 116 (1) Represents outstanding options reduced by expected forfeitures for options not fully vested. The weighted average grant date fair value of the stock options awarded during 2016, 2015 and 2014 was $15.90, $19.76 and $20.02, respectively. The aggregate intrinsic value, disclosed in the table above, represents the difference between L3’s closing stock price on the last trading day for the period, and the exercise price, multiplied by the number of in-the-money stock options. The total intrinsic value of stock options exercised, based on the difference between the L3’s stock price at the time of exercise and the related exercise price, was $34 million, $35 million and $43 million for the years ended December 31, 2016, 2015 and 2014, respectively. At December 31, 2016, unrecognized compensation costs related to stock options were $9 million ($6 million after income taxes), which are expected to be recognized over a weighted average remaining period of 1.4 years. The actual income tax benefit realized related to compensation deductions arising from the exercise of stock options by the Company’s employees totaled $12 million, $13 million and $14 million for the years ended December 31, 2016, 2015 and 2014, respectively. Stock Option Fair Value Estimation Assumptions. • Expected Holding Period. • Expected Volatility. • Expected Dividend Yield. • Risk-Free Interest Rates. Changes in assumptions can materially impact the estimated fair value of stock options. The weighted average assumptions used in the valuation model are presented in the table below. 2016 Grants 2015 Grants 2014 Grants Expected holding period (in years) 5.0 5.0 5.5 Expected volatility 21.3 % 21.4 % 24.4 % Expected dividend yield 2.8 % 2.4 % 2.7 % Risk-free interest rate 1.1 % 1.5 % 1.7 % Restricted Stock Units. The table below presents a summary of the Company’s nonvested restricted stock unit awards at December 31, 2016 and changes during the year then ended. Number of Shares Weighted Average Grant Date Fair Value (in thousands) Nonvested balance at January 1, 2016 1,171.9 $ 102.91 Granted 397.6 116.72 Vested (478.3 ) 76.83 Forfeited (113.3 ) 111.89 Nonvested balance at December 31, 2016 977.9 $ 120.24 At December 31, 2016, total unrecognized compensation costs related to nonvested restricted stock unit awards were $38 million ($24 million after income taxes) and are expected to be recognized over a weighted average remaining period of 1.2 years. The total fair value of restricted stock unit awards vested during the years ended December 31, 2016, 2015 and 2014 as of their vesting dates was $57 million, $82 million and $66 million, respectively. Performance Units. During the years ended December 31, 2016, 2015, and 2014, the Company granted performance unit awards with a weighted average grant date fair value per unit of $116.20, $129.03 and $113.67, respectively. All the awards granted in 2016, 2015, and 2014 have performance conditions based on L3’s diluted EPS. The performance periods for the awards began on January 1 of the applicable grant year and end on December 31 of the year corresponding to a three-year performance period. Units earned under the awards are convertible into shares of L3’s common stock. At December 31, 2016, total unrecognized compensation costs related to the awards were $6 million ($4 million after income taxes) and are expected to be recognized over a weighted average remaining period of 1.6 years. The table below presents a summary of the Company’s performance unit awards based on expected performance at December 31, 2016 and changes during the year then ended. Payable in Shares (EPS) Number of Units Weighted Average Grant Date Fair Value (in thousands) Outstanding at January 1, 2016 39.6 $ 121.27 Granted 51.9 116.20 Increase due to expected performance 35.6 127.14 Vested — — Forfeited (2.4 ) 121.72 Outstanding at December 31, 2016 124.7 $ 120.83 The performance period for awards granted in 2014 ended on December 31, 2016. Based on L3’s cumulative diluted EPS during the performance period, no performance units were earned by the participants on December 31, 2016. Employee Stock Purchase Plan. At December 31, 2016, 3.7 million shares were available for future issuance under the 2009 ESPP (i.e., excluding the effect of shares issued in January 2017 as described below). In July 2016, the Company issued 0.1 million shares under the 2009 ESPP at an average price of $137.87 per share, which covered employee contributions for the six months ended June 30, 2016. In January 2017, the Company issued 0.1 million shares under the 2009 ESPP at an average price of $144.73 per share, which covered employee contributions for the six months ended December 31, 2016. The 5% discount is not recognized as compensation expense in accordance with the accounting standard for share-based compensation expense. Award Modifications

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies [Abstract]
Commitments and Contingencies	18. Commitments and Contingencies Non-Cancelable Operating Leases The Company leases certain facilities and equipment under agreements expiring at various dates through 2033. Certain leases contain renewal options or escalation clauses providing for increased rental payments based upon maintenance, utility and tax increases. No lease agreement imposes a restriction on the Company’s ability to pay dividends, engage in debt or equity financing transactions, or enter into further lease agreements. The following table presents future minimum payments under non-cancelable operating leases with initial or remaining terms in excess of one year at December 31, 2016. Real Estate Equipment Total (in millions) 2017 $ 94 $ 5 $ 99 2018 81 3 84 2019 63 2 65 2020 90 — 90 2021 45 — 45 Thereafter 213 — 213 Total minimum payments required 586 10 596 Less: Sublease rentals under non-cancelable leases 10 — 10 Net minimum payments required $ 576 $ 10 $ 586 Rent expense was $101 million for 2016, $104 million for 2015, and $117 million for 2014. Sublease rental income was $2 million for 2016, and $2 million for 2015 and $1 million for 2014, respectively. Letters of Credit The Company enters into standby letters of credit with financial institutions covering performance and financial guarantees pursuant to contractual arrangements with certain customers. The Company had total outstanding letters of credit aggregating to $402 million and $425 million at December 31, 2016 and 2015, respectively. The Company had the full availability of its $1 billion Credit Facility at December 31, 2016. These letters of credit may be drawn upon in the event of the Company’s nonperformance. Guarantees The Company, from time to time, enters into contractual guarantees that arise in connection with its business acquisitions, dispositions, and other contractual arrangements in the normal course of business. In connection with the spin-off of Engility in 2012, L3 entered into a Distribution Agreement and several other agreements that govern certain aspects of L3’s relationship with Engility, including employee matters, tax matters, transition services, and the future supplier/customer relationship between L3 and Engility. These agreements generally provide cross-indemnities that, except as otherwise provided, are principally designed to place the financial responsibility for the obligations and liabilities of each entity with that respective entity. Engility has joint and several liability with L3 to the U.S. Internal Revenue Service (IRS) for the consolidated U.S. Federal income taxes of L3’s consolidated group for taxable periods in which Engility was a part of that group. However, the Tax Matters Agreement specifies the portion of this tax liability for which L3 and Engility will each bear responsibility, and L3 and Engility have agreed to indemnify each other against any amounts for which the other is not responsible. The Tax Matters Agreement also allocates responsibility between L3 and Engility for other taxes, including special rules for allocating tax liabilities in the event that the spin-off is determined not to be tax-free. Though valid as between the parties, the Tax Matters Agreement is not binding on the IRS. The Company has three existing real estate lease agreements, which include residual guarantee amounts, expiring on August 31, 2020 and are accounted for as operating leases. On or before the lease expiration date, the Company can exercise options under the lease agreements to renew the leases, purchase the properties for $45 million, or sell the properties on behalf of the lessor (the “Sale Option”). If the Company elects the Sale Option, the Company must pay the lessor a residual guarantee amount of $39 million for the properties, on or before the lease expiration date. In addition, at the time the properties are sold, the Company must pay the lessor a supplemental rent payment equal to the gross sales proceeds in excess of the residual guarantee, provided that such amount shall not exceed $6 million. For these real estate lease agreements, if the gross sales proceeds are less than the sum of the residual guarantee amount and the supplemental rent payment, the Company is required to pay a supplemental rent payment to the extent the reduction in the fair value of the properties is demonstrated by an independent appraisal to have been caused by the Company’s failure to properly maintain the properties. The aggregate residual guarantee amounts equal $39 million and are included in the future minimum payments under non-cancelable real estate operating lease payments relating to the expiration dates of such leases. The Company has a contract to provide and operate a full-service training facility for the U.S. Air Force (USAF), including simulator systems adjacent to a USAF base in Oklahoma. The Company acted as the construction agent on behalf of the third-party owner-lessors for procurement and construction for the simulator systems, which were completed and delivered in August 2002. The Company, as lessee, entered into operating lease agreements for a term of 15 years for the simulator systems with the owner-lessors. At the end of the lease term, the Company may elect to purchase the simulator systems at fair market value, which can be no less than $7 million and no greater than $21 million. If the Company does not elect to purchase the simulator systems on the date of expiration (during the first quarter of 2018), the Company must pay to the lessor, as additional rent, $7 million and return the simulator systems to the lessors. Environmental Matters Management continually assesses the Company’s obligations with respect to applicable environmental protection laws, including those obligations assumed in connection with certain business acquisitions. While it is difficult to determine the timing and ultimate cost to be incurred by the Company in order to comply with these laws, based upon available internal and external assessments, with respect to those environmental loss contingencies of which management is aware, the Company believes that there are no environmental loss contingencies that, individually or in the aggregate, would be material to the Company’s consolidated results of operations. The Company accrues for these contingencies when it is probable that a liability has been incurred and the amount of the liability can be reasonably estimated. 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 7. Amounts recoverable from insurance contracts or third parties are recorded as assets when deemed probable. At December 31, 2016, 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. SEC Inquiry Resolution. 401(k) Plan Class Action Derivative Action. HVC Alkmaar

Pensions and Other Employee Ben

Pensions and Other Employee Benefits	12 Months Ended
	Dec. 31, 2016
Pensions and Other Employee Benefits [Abstract]
Pensions and Other Employee Benefits	19. Pensions and Other Employee Benefits The following table summarizes changes in the benefit obligations, the plan assets and funded status for all of the Company’s pension and postretirement benefit plans, as well as the aggregate balance sheet impact. Pension Plans Postretirement Benefit Plans 2016 2015 2016 2015 (in millions) Change in benefit obligation: Benefit obligation at the beginning of the year $ 3,448 $ 3,663 $ 184 $ 199 Service cost 108 123 2 3 Interest cost 135 149 6 7 Plan participants’ contributions 2 2 4 4 Amendments 15 — (3 ) — Actuarial loss (gain) 167 (261 ) (3 ) (12 ) Foreign currency exchange rate changes 9 (53 ) — (4 ) Curtailments, settlements and special termination benefits 2 3 — — Business divestiture — (59 ) — — Benefits paid (128 ) (119 ) (13 ) (13 ) Benefit obligation at the end of the year $ 3,758 $ 3,448 $ 177 $ 184 Change in plan assets: Fair value of plan assets at the beginning of the year $ 2,552 $ 2,570 $ 57 $ 60 Actual return on plan assets 189 54 5 — Employer contributions 97 97 7 6 Plan participants’ contributions 2 2 4 4 Foreign currency exchange rate changes 9 (52 ) — — Benefits paid (128 ) (119 ) (13 ) (13 ) Fair value of plan assets at the end of the year $ 2,721 $ 2,552 $ 60 $ 57 Unfunded status at the end of the year $ (1,037 ) $ (896 ) $ (117 ) $ (127 ) Assets and (liabilities) recognized on the consolidated balance sheets consist of: Non-current assets $ 37 $ 37 $ — $ — Current liabilities (6 ) (5 ) (8 ) (8 ) Non-current liabilities (1,068 ) (928 ) (109 ) (119 ) $ (1,037 ) $ (896 ) $ (117 ) $ (127 ) The table below summarizes the net loss and prior service cost balances at December 31, in the accumulated other comprehensive loss account, before related tax effects, for all of the Company’s pension and postretirement benefit plans. Pension Plans Postretirement Benefit Plans 2016 2015 2016 2015 (in millions) Net loss (gain) $ 896 $ 768 $ (12 ) $ (10 ) Prior service cost (credit) 14 — (4 ) (3 ) Total amount recognized $ 910 $ 768 $ (16 ) $ (13 ) The aggregate accumulated benefit obligation (ABO) for all of the Company’s pension plans was $3,413 million at December 31, 2016 and $3,120 million at December 31, 2015. The table below presents information for the pension plans with an ABO in excess of the fair value of plan assets at December 31, 2016 and 2015. Pension Plans 2016 2015 (in millions) Projected benefit obligation $ 3,528 $ 3,232 Accumulated benefit obligation $ 3,192 $ 2,913 Fair value of plan assets $ 2,456 $ 2,302 The table below summarizes the weighted average assumptions used to determine the benefit obligations for the Company’s pension and postretirement plans disclosed at December 31, 2016 and 2015. Pension Plans Postretirement Benefit Plans 2016 2015 2016 2015 Benefit obligations: Discount rate 4.41 % (1) 4.67 % (1) 4.05 % (2) 4.22 % (2) Rate of compensation increase 3.50 % (3) 3.50 % (3) (1) The weighted average discount rate assumptions used at December 31, 2016 and 2015 were comprised of separate assumptions determined by country of 4.46% and 4.73% for the U.S. based plans, respectively, and 3.80% and 3.93% for the Canadian based plans, respectively. (2) The weighted average discount rate assumptions used at December 31, 2016 and 2015 were comprised of separate assumptions determined by country of 4.11% and 4.28% for the U.S. based plans, respectively, and 3.64% and 3.74% for the Canadian based plans, respectively. (3) The weighted average rate of compensation increase assumptions were comprised of separate assumptions determined by country of 3.5% for both the U.S. based plans and Canadian based plans at December 31, 2016 and 2015. The following table summarizes the components of net periodic benefit cost for the Company’s pension and postretirement benefit plans for the years ended December 31, 2016, 2015 and 2014. Pension Plans Postretirement Benefit Plans 2016 2015 2014 2016 2015 2014 (in millions) Components of net periodic benefit cost: Service cost $ 108 $ 123 $ 106 $ 2 $ 3 $ 3 Interest cost 135 149 147 6 7 8 Expected return on plan assets (200 ) (205 ) (193 ) (4 ) (5 ) (4 ) Amortization of prior service cost (credits) — 1 2 (2 ) (2 ) (2 ) Amortization of net loss (gain) 52 68 17 (2 ) — (2 ) Curtailment or settlement loss (gain) 2 3 1 — — (1 ) Net periodic benefit cost $ 97 $ 139 $ 80 $ — $ 3 $ 2 In 2016, the Company changed the approach used to measure the service and interest components of expense for all of its pension and postretirement benefit plans. For fiscal 2015 and previous periods, the Company measured the service and interest cost components using a single weighted-average discount rate derived from the yield curve used to measure the benefit obligations at the beginning of the period. Beginning in fiscal 2016, the Company elected to use a spot rate approach for its plans in the measurement of the components of benefit cost by applying specific spot rates along that yield curve to the relevant projected cash flows, as the Company believes the new approach provides a more precise measurement of service and interest costs. This change does not affect the measurement of the Company’s total benefit obligation. The Company has accounted for this change prospectively as a change in accounting estimate. The following table summarizes the other changes in plan assets and benefit obligations recognized in other comprehensive income for the Company’s pension and postretirement benefit plans for the years ended December 31, 2016, 2015 and 2014. Pension Plans Postretirement Benefit Plans 2016 2015 2014 2016 2015 2014 (in millions) Other changes in plan assets and benefit obligations recognized in other comprehensive income: Net loss (gain) $ 179 $ (132 ) $ 560 $ (4 ) $ (7 ) $ 5 Prior service cost (credit) 15 — 1 (2 ) — (1 ) Amortization of net (loss) gain (52 ) (68 ) (17 ) 2 — 2 Amortization of prior service (cost) credit — (1 ) (2 ) 2 2 2 Total recognized in other comprehensive income 142 (201 ) 542 (2 ) (5 ) 8 Total recognized in net periodic benefit cost and other comprehensive income $ 239 $ (62 ) $ 622 $ (2 ) $ (2 ) $ 10 The following table summarizes the amounts expected to be amortized from accumulated OCI and recognized as components of net periodic benefit costs during 2017. Pension Plans Postretirement Benefit Plans Total (in millions) Net loss (gain) $ 62 $ (2 ) $ 60 Prior service cost (credit) 1 (1 ) — $ 63 $ (3 ) $ 60 The table below summarizes the weighted average assumptions used to determine the net periodic benefit cost for the years ended December 31, 2016, 2015 and 2014. Pension Plans Postretirement Benefit Plans 2016 2015 2014 2016 2015 2014 Discount rates: Benefit obligation 4.67 % (1) 4.14 % (1) 5.03 % (1) 4.22 % (4) 3.70 % (4) 4.43 % (4) Service cost 4.83 % — (5) — (5) 4.37 % — (5) — (5) Interest cost 3.95 % — (5) — (5) 3.26 % — (5) — (5) Expected long-term return on plan assets 7.92 % (2) 8.14 % (2) 8.13 % (2) 7.42 % 7.65 % 7.64 % Rate of compensation increase 3.50 % (3) 3.50 % (3) 3.50 % (3) (1) The weighted average discount rate assumptions used for the years ended December 31, 2016, 2015, and 2014 were comprised of separate assumptions determined by country of 4.73%, 4.20% and 5.10% for the U.S. based plans and 3.93%, 3.90% and 4.70% for the Canadian based plans, respectively. (2) The weighted average expected long-term return on plan assets assumptions used were comprised of separate assumptions determined by country of 8.00% and 8.25% for the U.S. based plans for the years ended December 31, 2016 and 2015, respectively, and 7.25% for the Canadian based plans for the years ended December 31, 2016, and 2015. (3) The weighted average rate of compensation increase assumptions used for the years ended December 31, 2016, 2015 and 2014 were comprised of separate assumptions determined by country of 3.50% for both the U.S and Canadian based plans. (4) The weighted average discount rate assumptions used for the years ended December 31, 2016, 2015 and 2014 were comprised of separate assumptions determined by country of 4.28%, 3.70% and 4.40% for the U.S. based plans and 3.74%, 3.70% and 4.60% for the Canadian based plans, respectively. (5) Not applicable as the Company changed to the spot rate approach beginning in 2016 as described above. The expected long-term return on plan assets assumption represents the average rate that the Company expects to earn over the long-term on the assets of the Company’s benefit plans, including those from dividends, interest income and capital appreciation. The Company utilizes a third-party consultant to assist in the development of the expected long-term return on plan assets, which is based on expectations regarding future long-term rates of return for the plans’ investment portfolio, with consideration given to the allocation of investments by asset class and historical rates of return for each individual asset class. The Company utilizes a building block methodology that utilizes historical and forward looking rates of return for each asset class and takes into account expected returns above inflation and risk premium. These long-term rates of return are then applied to the target portfolio allocations that are generally aligned with the actual asset allocations of our plans to develop the expected long-term rate of return. The annual increase in cost of benefits (health care cost trend rate) for the Company’s U.S. based plans covering retirees under 65 years of age is assumed to be an average of 7.0% in 2017 and is assumed to gradually decrease to a rate of 5.0% in 2021 and thereafter. The health care cost trend rate for the Company’s U.S. based plans covering retirees over 65 years of age is assumed to be an average of 8.5% in 2017 and is assumed to gradually decrease to a rate of 5.0% in 2024 and thereafter. The health care cost trend rate for the Company’s Canadian based plans is assumed to be an average of 6.5% in 2017 and is assumed to gradually decrease to a rate of 5.0% in 2023 and thereafter. Health care cost trend assumptions are based on (1) observed or expected short term rates of increase for different types of health models based on actual claims experience and benchmarking, and (2) a reasonable estimate of an appropriate, sustainable level of health care cost trend in the future, weighting the factors that primarily influence trends, which are price inflation and cost leveraging benefit plan features. Assumed health care cost trend rates can have a significant effect on amounts reported for postretirement medical benefit plans. A one percentage point change in the assumed health care cost trend rates would have the following effects: 1 percentage point Increase Decrease (in millions) Effect on total service and interest cost $ — $ — Effect on postretirement benefit obligations $ 5 $ (4 ) Plan Assets. The Committee retains a professional investment consultant to advise the Committee and help ensure that the above policies and strategies are met. The Committee does not actively manage the day to day operations and selection process of individual securities and investments, as it retains the professional services of qualified investment management organizations to fulfill those tasks. Qualified investment management organizations are evaluated on several criteria for selection, with a focus on the investment management organizations’ demonstrated capability to achieve results that will meet or exceed the investment objectives they have been assigned and conform to the policies established by the Committee. While the investment management organizations have investment discretion over the assets placed under their management, the Committee provides each investment manager with specific investment guidelines relevant to its asset class. The Committee has established the allowable range that the plans’ assets may be invested in for each major asset category. In addition, the Committee has established guidelines regarding diversification within asset categories to limit risk and exposure to a single or limited number of securities. The investments of the plans’ include a diversified portfolio of both equity and fixed income investments. Equity investments are further diversified across U.S. and non-U.S. stocks, small to large capitalization stocks, and growth and value stocks. Fixed income assets are diversified across U.S. and non-U.S. issuers, corporate and governmental issuers, and credit quality. The plan also invests in real estate through publicly traded real estate securities. Derivatives may be used only for hedging purposes or to create synthetic long positions. The plans are prohibited from directly owning commodities, unregistered securities, restricted stock, private placements, or interests in oil, gas, mineral exploration, or other development programs. Further, short selling or utilizing margin buying for investment purposes is prohibited. The table below presents the allowable range for each major category of the plans’ assets at December 31, 2016 as well as the Company’s pension plan and postretirement benefit plan weighted-average asset allocations at December 31, 2016 and 2015, by asset category. U.S. Canada Asset Category Range 2016 2015 Range 2016 2015 Domestic equity (1) 30%-60% 55 % 52 % — 15 % 13 % International equity (2) 10%-20% 10 11 — 62 62 Total equities 45%-75% 65 63 40%-80% 77 75 Fixed income securities 20%-40% 22 22 — 13 16 Other, primarily cash and cash equivalents 0%-15% 5 8 — 10 9 Total fixed income securities and cash and cash equivalents — 27 30 20%-60% 23 25 Real estate securities 0%-15% 8 7 — — — Total 100 % 100 % 100 % 100 % (1) Domestic equities for Canadian plans refers to equities of Canadian companies. (2) International equities for Canadian plans includes equities of U.S. companies. The Committee regularly monitors the investment of the plans’ assets to ensure that the actual investment allocation remains within the established range. The Committee also regularly measures and monitors investment risk through ongoing performance reporting and investment manager reviews. Investment manager reviews include assessing the managers’ performance versus the appropriate benchmark index both in the short and long-term period, performance versus peers, and an examination of the risk the managers assumed in order to achieve rates of return. The table below presents the fair value of the Company’s pension plans’ assets by asset category segregated by level within the fair value hierarchy, as described below. U.S. Pension Plans’ Assets Canadian Pension Plans’ Assets Fair Value Measured at December 31, 2016 Fair Value Measured at December 31, 2016 Asset Category Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in millions) Equity securities (1) U.S. Equity $ 1,331 $ — $ — $ 1,331 $ 79 $ — $ — $ 79 International Equity 85 — — 85 104 — — 104 Fixed Income — Investment Grade (2) 255 159 — 414 — — — — Fixed Income — High Yield (3) — 136 — 136 — — — — Real Estate Investment Trusts (4) 193 — — 193 — — — — Other (5) — 114 — 114 5 27 — 32 Total assets at fair value $ 1,864 $ 409 $ — $ 2,273 $ 188 $ 27 $ — $ 215 Liabilities for unsettled trades, net (23 ) — Other investments measured at net asset value (6)(7) 171 85 Total $ 2,421 $ 300 U.S. Pension Plans’ Assets Canadian Pension Plans’ Assets Fair Value Measured at December 31, 2015 Fair Value Measured at December 31, 2015 Asset Category Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in millions) Equity securities (1) U.S. Equity $ 1,200 $ — $ — $ 1,200 $ 73 $ — $ — $ 73 International Equity 79 — — 79 91 — — 91 Fixed Income — Investment Grade (2) 237 163 — 400 — — — — Fixed Income — High Yield (3) — 114 — 114 — — — — Real Estate Investment Trusts (4) 170 — — 170 — — — — Other (5) — 166 — 166 6 21 — 27 Total assets at fair value $ 1,686 $ 443 $ — $ 2,129 $ 170 $ 21 $ — $ 191 Liabilities for unsettled trades, net (30 ) — Other investments measured at net asset value (6)(7) 170 92 Total $ 2,269 $ 283 (1) Equity securities consist of investments in common stock of U.S. and international companies. The fair value of equity securities is based on quoted market prices available in active markets at the close of a trading day, primarily the New York Stock Exchange (NYSE), National Association of Securities Dealers Automated Quotations (NASDAQ), and various international exchanges. (2) Approximately 62% and 59% at December 31, 2016 and 2015, respectively, of U.S. plan assets that are invested in the Fixed Income — Investment Grade asset category consist of a mutual fund offered by a registered investment company (the Fund) and fixed income securities. The Fund invests in investment grade fixed income securities, mortgaged-backed securities, U.S. treasury and agency bonds and corporate bonds. These investments are classified by the Company as a Level 1 measurement within the fair value hierarchy, as the mutual fund trades on an active market and daily, quoted prices are available. The remaining 38% and 41% at December 31, 2016 and 2015, respectively, of U.S. plan assets are fixed income securities, primarily investment grade corporate bonds from various industries held directly by the plan. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs and are classified as Level 2. (3) Fixed Income — High Yield consists of investments in corporate high-yield bonds from various industries. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs. (4) Real Estate Investment Trusts (REITs) consist of securities that trade on the major exchanges and invest directly in real estate, either through properties or mortgages. (5) Other consists primarily of: (1) money market accounts, which invest primarily in short-term, high quality money market securities such as government obligations, commercial paper, time deposits and certificates of deposit, and are classified as Level 2, and (2) cash, which is classified as Level 1. (6) In accordance with ASU 2015-07, certain investments that are measured at fair value using the net asset value (NAV) per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statements of financial position. (7) All of the U.S. plans other investments measured using NAV at December 31, 2016 and 2015 and approximately 55% and 52% at December 31, 2016 and 2015, respectively, of the Canadian plans other investments measured using NAV consist of a regulated commingled equity trust fund, for which fair value is based on the NAV at the end of each month. The NAV is calculated by the fund manager based on the fair value of the fund’s holdings, primarily equity securities traded in active markets, determined as of the end of each month as a practical expedient to estimating fair value. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Withdrawals are permitted, with notice by the 20th day of each month, based on NAV. Approximately 45% and 48% at December 31, 2016 and 2015, respectively, of the Canadian plans other investments measured using NAV are invested in regulated commingled bond funds (the “Bond Funds”). As these Bond Funds do not trade in an active market, the fair value is based on NAVs calculated by fund managers based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs as a practical expedient to estimating fair value and classified as Level 2. Withdrawals are permitted monthly, with notice between 0 and 3 days of the transaction date, based on NAV. The table below presents the fair value of the Company’s postretirement benefit plans’ assets by asset category segregated by level within the fair value hierarchy, as described below. Postretirement Benefit Plans’ Assets Fair Value Measured at December 31, 2016 Fair Value Measured at December 31, 2015 Asset Category Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in millions) Equity securities (1) U.S. Equity $ 37 $ — $ — $ 37 $ 35 $ — $ — $ 35 International Equity 1 — — 1 1 — — 1 Fixed Income — Investment Grade (2) 8 3 — 11 8 3 — 11 Fixed Income — High Yield (3) — 2 — 2 — 2 — 2 Real Estate Investment Trusts (4) 3 — — 3 3 — — 3 Other (5) — 3 — 3 — 2 — 2 Total assets at fair value $ 49 $ 8 $ — $ 57 $ 47 $ 7 $ — $ 54 Other investments measured at net asset value (6)(7) 3 3 Total $ 60 $ 57 (1) Equity securities consist of investments in common stock of U.S. and international companies. The fair value of equity securities is based on quoted market prices available in active markets at the close of a trading day, primarily the NYSE, NASDAQ, and various international exchanges. (2) Approximately 73% at December 31, 2016 and 2015 of the postretirement benefit plan assets that are invested in the Fixed Income — Investment Grade asset category consist of the Fund and fixed income securities. The Fund invests in investment grade fixed income securities, mortgaged-backed securities, U.S. treasury and agency bonds and corporate bonds. These investments are classified by the Company as a Level 1 measurement within the fair value hierarchy as the mutual fund trades on an active market and daily, quoted prices are available. The remaining 27% at December 31, 2016 and 2015 of the postretirement benefit plan assets are fixed income securities, primarily investment grade corporate bonds from various industries held directly by the plan. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs and are classified as Level 2. (3) Fixed Income — High Yield consists of investments in corporate high-yield bonds from various industries. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs. (4) REITs consist of securities that trade on the major exchanges and invest directly, either through properties or mortgages. (5) Other consists primarily of money market accounts, which invest primarily in short-term, high quality money market securities such as government obligations, commercial paper, time deposits and certificates of deposit. (6) In accordance with ASU 2015-07, certain investments that are measured at fair value using the NAV per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statements of financial position. (7) All of the postretirement benefit plans other investments measured using NAV at December 31, 2016 and 2015 consist of a regulated commingled equity trust fund, which fair value is based on NAV at the end of each month. The NAV is calculated by the fund manager based on the fair value of the fund’s holdings, primarily equity securities traded in active markets, determined as of the end of each month as a practical expedient to estimating fair value. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Withdrawals are permitted, with notice by the 20th day of each month, based on NAV. Contributions. Estimated Future Benefit Payments. Postretirement Benefits Pension Benefits Benefit Payments Subsidy Receipts (in millions) 2017 $ 162 $ 13 $ — 2018 156 13 — 2019 162 14 — 2020 171 14 — 2021 175 14 — Years 2022-2026 1,001 65 1 Employee Savings Plans. Multiemployer Benefit Plans. Under these plans, the Company contributed cash and recorded expenses for each of its individually significant plans and all of its other plans in aggregate as noted in the table below. EIN/Pension Plan Number Pension Protection Act Zone Status (1) FIP/RP (2) Status Pending/ Implemented Contributions by L3 Surcharge Imposed Expiration Date of Collective- Bargaining Agreement Pension Fund 2016 2015 2016 2015 2014 (in millions) IAM National Pension Fund 51-6031295/002 Green Green No $ 26 (3) $ 23 (4) $ 19 (4) No 4/9/2017 to (5) Other Pension Funds (6) — — — Total contributions $ 26 $ 23 $ 19 (1) A zone status rating of green indicates the plan is at least 80% funded. (2) Funding improvement plan or rehabilitation plan. (3) At the date the audited financial statements for the Company were issued, the Form 5500 for the plan year ended December 31, 2016 was not available. (4) Represents 5% of total plan contributions for the years ended December 31, 2015 and 2014 based on Form 5500. (5) The Company is a party to multiple bargaining agreements for multiple projects that require contributions into the IAM National Pension Fund. The most significant of these agreements, expiring April 28, 2019, covers multiple programs in the Company’s Aerospace Systems reportable segment and represents 63% of 2016 contributions. (6) Consists of three pension funds in which the Company’s contributions are individually, and in the aggregate, insignificant.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	12 Months Ended
	Dec. 31, 2016
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	20. Supplemental Cash Flow Information Year Ended December 31, 2016 2015 2014 (in millions) Interest paid on outstanding debt $ 162 $ 182 $ 176 Income tax payments $ 120 $ 132 $ 129 Income tax refunds $ 8 $ 8 $ 9

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2016
Segment Information [Abstract]
Segment Information	21. Segment Information The Company has three 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, gains or losses related to business divestitures, and certain other items that are excluded by management for purposes of evaluating the operating performance of the Company’s business segments. Certain Corporate expenses of $15 million and $16 million for the years ended December 31, 2015 and 2014, respectively, that had previously been allocated to the NSS business were retained by the Company and were allocated to L3’s three reportable segments. The tables below present net sales, operating income (loss), depreciation and amortization, capital expenditures and total assets by reportable segment. Year Ended December 31, 2016 2015 2014 (in millions) Net Sales Products Electronic Systems $ 3,293 $ 3,390 $ 3,685 Aerospace Systems 1,662 1,661 1,722 Communication Systems 1,585 1,648 1,546 Elimination of intercompany sales (98 ) (110 ) (114 ) Total products sales 6,442 6,589 6,839 Services Electronic Systems $ 1,042 $ 999 $ 1,057 Aerospace Systems 2,580 2,503 2,604 Communication Systems 488 441 539 Elimination of intercompany sales (41 ) (66 ) (53 ) Total services sales 4,069 3,877 4,147 Consolidated total $ 10,511 $ 10,466 $ 10,986 Operating income Electronic Systems $ 518 $ 489 $ 533 Aerospace Systems 289 205 283 Communication Systems 201 196 196 Segment total 1,008 890 1,012 Loss related to business divestitures (1) — (31 ) — Goodwill impairment charges (2) — (384 ) — Consolidated total $ 1,008 $ 475 $ 1,012 Year Ended December 31, 2016 2015 2014 (in millions) Depreciation and amortization Electronic Systems $ 105 $ 110 $ 123 Aerospace Systems 54 50 40 Communication Systems 47 50 51 Consolidated total $ 206 $ 210 $ 214 Capital Expenditures Electronic Systems $ 113 $ 99 $ 80 Aerospace Systems 56 55 59 Communication Systems 37 37 29 Corporate 10 6 6 Consolidated total $ 216 $ 197 $ 174 Total Assets Electronic Systems $ 6,802 $ 6,426 $ 6,281 Aerospace Systems 2,535 2,630 3,011 Communication Systems 2,031 1,984 2,025 Corporate 497 365 566 Assets held for sale — — 547 Assets of discontinued operations — 664 1,262 Consolidated total $ 11,865 $ 12,069 $ 13,692 (1) See Note 3 for information regarding the Company’s business divestitures. (2) Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information. Corporate assets not allocated to the reportable segments primarily include cash and cash equivalents, corporate office fixed assets, and deferred income tax assets. The table below presents property, plant and equipment, net by geographic area. Year Ended December 31, 2016 2015 (in millions) United States $ 974 $ 971 All Other 147 126 Total $ 1,121 $ 1,097 The Company’s sales attributable to U.S. and international customers, based on location of the customer, are summarized in the table below. Year Ended December 31, 2016 2015 2014 (in millions) U.S. $ 8,199 $ 7,908 $ 8,051 International: United Kingdom 331 336 335 Canada 297 281 289 Australia 254 321 254 Saudi Arabia 159 201 160 South Korea 127 207 226 Japan 81 95 124 France 75 62 74 Other 988 1,055 1,473 Total international 2,312 2,558 2,935 Consolidated $ 10,511 $ 10,466 $ 10,986 Net sales to principal customers are summarized in the table below. Year Ended December 31, 2016 2015 2014 (in millions) U.S. Government agencies (1) $ 7,649 $ 7,291 $ 7,464 Commercial 1,282 1,376 1,656 Foreign governments (1) 1,580 1,799 1,866 Consolidated $ 10,511 $ 10,466 $ 10,986 (1) Includes sales for which the Company is the prime contractor as well as sales based on the ultimate end customer for which the Company is a subcontractor.

Employee Severance and Terminat

Employee Severance and Termination Costs	12 Months Ended
	Dec. 31, 2016
Employee Severance and Termination Costs [Abstract]
Employee Severance and Termination Costs	22. Employee Severance and Termination 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 employee severance and other termination costs of $17 million with respect to approximately 700 employees during the year ended December 31, 2016, $18 million with respect to approximately 800 employees during the year ended December 31, 2015 and $29 million with respect to approximately 1,800 employees during the year ended December 31, 2014. Employee severance and other termination costs are reported within cost of sales on the consolidated statements of operations. The remaining balance to be paid in connection with these initiatives was $9 million at December 31, 2016, which is expected to be paid in 2017, and $9 million at December 31, 2015, which was paid during 2016. Employee severance and other termination costs incurred by reportable segment are presented in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Electronic Systems $ 8 $ 8 $ 16 Aerospace Systems 2 4 5 Communication Systems 7 6 8 Consolidated $ 17 $ 18 $ 29

Unaudited Quarterly Financial D

Unaudited Quarterly Financial Data	12 Months Ended
	Dec. 31, 2016
Unaudited Quarterly Financial Data [Abstract]
Unaudited Quarterly Financial Data	23. Unaudited Quarterly Financial Data Unaudited summarized financial data by quarter for the years ended December 31, 2016 and 2015 is presented in the table below. The Company’s unaudited quarterly results of operations are affected, significantly in some periods, by our business acquisitions and divestitures. See Note 3. First Quarter Second Quarter Third Quarter Fourth Quarter (in millions, except per share data) 2016 Sales $ 2,353 $ 2,664 $ 2,505 $ 2,989 Operating income 252 247 215 294 Income from continuing operations 167 151 151 192 Net income 230 151 151 192 Net income attributable to L3 227 147 148 188 Basic EPS from continuing operations (1) 2.11 1.90 1.91 2.43 Basic EPS (1) 2.92 1.90 1.91 2.43 Diluted EPS from continuing operations (1) 2.08 1.88 1.88 2.38 Diluted EPS (1) 2.87 1.88 1.88 2.38 2015 Sales $ 2,488 $ 2,543 $ 2,564 $ 2,871 Operating income (loss) 187 153 231 (96 ) Income (loss) from continuing operations 105 120 128 (56 ) Net income (loss) 109 124 (296 ) (162 ) Net income (loss) attributable to L3 105 120 (299 ) (166 ) Basic earnings (loss) per share from continuing operations (1) 1.23 1.41 1.56 (0.76 ) Basic earnings (loss) per share (1) 1.28 1.46 (3.74 ) (2.11 ) Diluted earnings (loss) per share from continuing operations (1) 1.20 1.39 1.54 (0.76 ) Diluted earnings (loss) per share (1) 1.25 1.44 (3.68 ) (2.11 ) (1) EPS in each quarter is computed using the weighted-average number of shares outstanding during that quarter, while EPS for the full year is computed using the weighted-average number of shares outstanding during the year. Therefore, the sum of the four quarters’ EPS may not equal the full year computed EPS.

Financial Information of L3 and

Financial Information of L3 and Its Subsidiaries	12 Months Ended
	Dec. 31, 2016
Financial Information of L3 and Its Subsidiaries [Abstract]
Financial Information of L3 and Its Subsidiaries	24. 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 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. In lieu of providing separate audited financial statements for the Guarantor Subsidiaries, the Company has included the accompanying condensed combining financial statements based on Rule 3-10 of SEC Regulation S-X. The Company does not believe that separate financial statements of the Guarantor Subsidiaries are material to users of the financial statements. The following 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 elimination of the holding company structure and the Merger discussed in Note 2, prior year amounts have been recast to conform to the current year presentation. L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) Condensed Combining Balance Sheets: 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 2,162 3,227 1,171 — 6,560 Other assets 705 591 312 — 1,608 Investment in and amounts due from consolidated subsidiaries 5,867 5,430 — (11,297 ) — Total assets $ 10,216 $ 10,846 $ 2,236 $ (11,433 ) $ 11,865 Current liabilities $ 789 $ 1,022 $ 460 $ (136 ) $ 2,135 Amounts due to consolidated subsidiaries — — 282 (282 ) — Other long-term liabilities 1,549 200 32 — 1,781 Long-term debt 3,325 — — — 3,325 Total liabilities 5,663 1,222 774 (418 ) 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 $ 2,236 $ (11,433 ) $ 11,865 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) At December 31, 2015: Current assets: Cash and cash equivalents $ 137 $ — $ 165 $ (95 ) $ 207 Billed receivables, net 278 297 171 — 746 Contracts in process 872 958 251 — 2,081 Other current assets 288 137 109 — 534 Assets of discontinued operations — 664 — — 664 Total current assets 1,575 2,056 696 (95 ) 4,232 Goodwill 2,318 2,973 990 — 6,281 Other assets 800 496 260 — 1,556 Investment in and amounts due from consolidated subsidiaries 5,609 3,739 111 (9,459 ) — Total assets $ 10,302 $ 9,264 $ 2,057 $ (9,554 ) $ 12,069 Current portion of long-term debt $ 499 $ — $ — $ — $ 499 Current liabilities 911 899 445 (95 ) 2,160 Liabilities of discontinued operations — 220 — — 220 Other long-term liabilities 1,410 195 29 — 1,634 Long-term debt 3,127 — — — 3,127 Total liabilities 5,947 1,314 474 (95 ) 7,640 L3 shareholders’ equity 4,355 7,950 1,583 (9,533 ) 4,355 Noncontrolling interests — — — 74 74 Total equity 4,355 7,950 1,583 (9,459 ) 4,429 Total liabilities and equity $ 10,302 $ 9,264 $ 2,057 $ (9,554 ) $ 12,069 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) Condensed Combining Statements of Operations: For the year ended December 31, 2016: Total net sales $ 3,388 $ 6,063 $ 1,379 $ (319 ) $ 10,511 Total cost of sales (3,078 ) (5,610 ) (1,134 ) 319 (9,503 ) Operating income 310 453 245 — 1,008 Interest expense (168 ) (1 ) — — (169 ) Interest and other income, net 11 1 6 — 18 Debt retirement charge (7 ) — — — (7 ) Income from continuing operations before income taxes 146 453 251 — 850 Provision for income taxes (32 ) (101 ) (56 ) — (189 ) Equity in net income of consolidated subsidiaries 596 — — (596 ) — Income from continuing operations 710 352 195 (596 ) 661 Income from discontinued operations, net of income tax — 63 — — 63 Net income 710 415 195 (596 ) 724 Net income attributable to noncontrolling interests — — — (14 ) (14 ) Net income attributable to L3 $ 710 $ 415 $ 195 $ (610 ) $ 710 Comprehensive income attributable to L3 $ 558 $ 425 $ 118 $ (543 ) $ 558 For the year ended December 31, 2015: Total net sales $ 3,580 $ 5,265 $ 1,935 $ (314 ) $ 10,466 Total cost of sales (3,283 ) (4,906 ) (1,701 ) 314 (9,576 ) (Loss) gain related to business divestitures (13 ) (31 ) 13 — (31 ) Goodwill impairment charges — (364 ) (20 ) — (384 ) Operating income (loss) 284 (36 ) 227 — 475 Interest expense (167 ) (1 ) (1 ) — (169 ) Interest and other income, net 16 — 1 — 17 Debt retirement charge (1 ) — — — (1 ) Income (loss) from continuing operations before income taxes 132 (37 ) 227 — 322 (Provision) benefit for income taxes (10 ) 3 (18 ) — (25 ) Equity in net loss of consolidated subsidiaries (362 ) — — 362 — (Loss) income from continuing operations (240 ) (34 ) 209 362 297 Loss from discontinued operations, net of income tax — (522 ) — — (522 ) Net (loss) income (240 ) (556 ) 209 362 (225 ) Net income attributable to noncontrolling interests — — — (15 ) (15 ) Net (loss) income attributable to L3 $ (240 ) $ (556 ) $ 209 $ 347 $ (240 ) Comprehensive (loss) income attributable to L3 $ (230 ) $ (560 ) $ 98 $ 462 $ (230 ) For the year ended December 31, 2014: Total net sales $ 3,586 $ 5,460 $ 2,218 $ (278 ) $ 10,986 Total cost of sales (3,255 ) (5,017 ) (1,980 ) 278 (9,974 ) Operating income 331 443 238 — 1,012 Interest expense (156 ) (2 ) — — (158 ) Interest and other income, net 15 — 3 — 18 Income from continuing operations before income taxes 190 441 241 — 872 Provision for income taxes (49 ) (115 ) (63 ) — (227 ) Equity in net income of consolidated subsidiaries 523 — — (523 ) — Income from continuing operations 664 326 178 (523 ) 645 Income from discontinued operations, net of income tax — 32 — — 32 Net income 664 358 178 (523 ) 677 Net income attributable to noncontrolling interests — — — (13 ) (13 ) Net income attributable to L3 $ 664 $ 358 $ 178 $ (536 ) $ 664 Comprehensive income attributable to L3 $ 190 $ 356 $ 47 $ (403 ) $ 190 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) Condensed Combining Statements of Cash Flows: For the year ended December 31, 2016: Operating activities: Net cash from operating activities from continuing operations $ 482 $ 542 $ 259 $ (186 ) $ 1,097 Investing activities: Business acquisitions, net of cash acquired (388 ) — — — (388 ) Proceeds from sale of business, net of closing date cash balances 563 — (2 ) — 561 Other investing activities (60 ) (86 ) (43 ) — (189 ) Net cash from (used in) investing activities from continuing operations 115 (86 ) (45 ) — (16 ) Financing activities: Proceeds from sale of senior notes 547 — — — 547 Redemption of senior notes (856 ) — — — (856 ) Common stock repurchased (373 ) — — — (373 ) Dividends paid on L3’s common stock (220 ) — — — (220 ) Other financing activities 459 (399 ) (159 ) 145 46 Net cash used in financing activities from continuing operations (443 ) (399 ) (159 ) 145 (856 ) Effect of foreign currency exchange rate changes on cash — — (13 ) — (13 ) Net decrease in cash and cash equivalents of discontinued operations — (56 ) — — (56 ) Net increase in cash 154 1 42 (41 ) 156 Cash and cash equivalents, beginning of the year 137 — 165 (95 ) 207 Cash and cash equivalents, end of the year $ 291 $ 1 $ 207 $ (136 ) $ 363 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) For the year ended December 31, 2015: Operating activities: Net cash from operating activities from continuing operations $ 616 $ 422 $ 216 $ (185 ) $ 1,069 Investing activities: Business acquisitions, net of cash acquired (320 ) — — — (320 ) Proceeds from sale of business, net of closing date cash balances 14 28 276 — 318 Other investing activities (84 ) (69 ) (37 ) — (190 ) Net cash (used in) from investing activities from continuing operations (390 ) (41 ) 239 — (192 ) Financing activities: Repurchases of senior notes (297 ) — — — (297 ) Common stock repurchased (740 ) — — — (740 ) Dividends paid on L3's common stock (214 ) — — — (214 ) Other financing activities 801 (434 ) (473 ) 152 46 Net cash used in financing activities from continuing operations (450 ) (434 ) (473 ) 152 (1,205 ) Effect of foreign currency exchange rate changes on cash — — (19 ) — (19 ) Net increase in cash and cash equivalents of discontinued operations — 51 — — 51 Change in cash balance in assets held for sale — 1 60 — 61 Net (decrease) increase in cash (224 ) (1 ) 23 (33 ) (235 ) Cash and cash equivalents, beginning of the year 361 1 142 (62 ) 442 Cash and cash equivalents, end of the year $ 137 $ — $ 165 $ (95 ) $ 207 For the year ended December 31, 2014: Operating activities: Net cash from operating activities from continuing operations $ 467 $ 571 $ 143 $ (93 ) $ 1,088 Investing activities: Business acquisitions, net of cash acquired (57 ) — — — (57 ) Other investing activities (58 ) (85 ) (21 ) — (164 ) Net cash used in investing activities from continuing operations (115 ) (85 ) (21 ) — (221 ) Financing activities: Proceeds from sale of senior notes 996 — — — 996 Redemption of CODES (935 ) — — — (935 ) Common stock repurchased (823 ) — — — (823 ) Dividends paid on L3's common stock (208 ) — — — (208 ) Other financing activities 721 (530 ) (164 ) 50 77 Net cash used in financing activities from continuing operations (249 ) (530 ) (164 ) 50 (893 ) Effect of foreign currency exchange rate changes on cash — — (17 ) — (17 ) Net increase in cash and cash equivalents of discontinued operations — 46 — — 46 Change in cash balance in assets held for sale — (1 ) (60 ) — (61 ) Net increase (decrease) in cash 103 1 (119 ) (43 ) (58 ) Cash and cash equivalents, beginning of the year 258 — 261 (19 ) 500 Cash and cash equivalents, end of the year $ 361 $ 1 $ 142 $ (62 ) $ 442

Summary of Significant Accoun34

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Summary of Significant Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation:
Accounting Estimates	Accounting Estimates: 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 $148 million, or 15%, of consolidated operating income ($1.22 per diluted share) for the year ended December 31, 2016, increases of $52 million, or 11%, of consolidated operating income ($0.45 per diluted share) for the year ended December 31, 2015, and increases of $72 million, or 7%, of consolidated operating income ($0.52 per diluted share) for the year ended December 31, 2014.
Revenue Recognition	Revenue Recognition: 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 contracts with multiple deliverables, the Company applies the separation and allocation guidance under the accounting standard for revenue arrangements with multiple deliverables, unless all the deliverables are covered by contract accounting standards, in which case the Company applies the separation and allocation guidance under contract accounting standards. Revenue arrangements with multiple deliverables are evaluated to determine if the deliverables should be separated into more than one unit of accounting. The Company recognizes revenue for each unit of accounting based on the revenue recognition policies discussed above. Sales and cost of sales in connection with contracts to provide services to the U.S. Government that contain collection risk because the contracts are incrementally funded and subject to the availability of funds appropriated, are deferred until a contract modification is obtained, indicating that adequate funds are available to the contract or task order.
Research and Development	Research and Development: Customer-funded research and development costs are incurred pursuant to contracts (revenue arrangements) to perform research and development activities according to customer specifications. These costs are not accounted for as research and development expenses, and are also not indirect contract costs. Instead, these costs are direct contract costs and are expensed to cost of sales when the corresponding revenue is recognized, which is generally as the research and development services are performed. Customer-funded research and development costs are substantially all incurred under cost-plus type contracts with the U.S. Government.
Product Warranties	Product Warranties: The table below presents the changes in the Company’s accrued product warranty costs. Year Ended December 31, 2016 2015 (in millions) Accrued product warranty costs (1) : Balance at January 1 $ 105 $ 93 Acquisitions during this period 3 1 Accruals for product warranties issued during the period 51 59 Changes to accruals for product warranties existing before January 1 — 2 Foreign currency translation adjustments (1 ) (2 ) Settlements made during the period (49 ) (48 ) Balance at December 31 $ 109 $ 105 (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.
Deferred Debt Issue Costs	Deferred Debt Issue Costs:
Pension Plan and Postretirement Benefit Plan Obligations	Pension Plan and Postretirement Benefit Plan Obligations: The Company also provides postretirement medical and life insurance benefits for retired employees and dependents at certain locations. Participants are eligible for these benefits when they retire from active service and meet the eligibility requirements for the Company’s pension plans. These benefits are funded primarily on a pay-as-you-go basis with the retiree generally paying a portion of the cost through contributions, deductibles and coinsurance provisions. In accordance with accounting standards for employee pension and postretirement benefits, the Company recognizes on a plan-by-plan basis the unfunded status of its pension and postretirement benefit plans in the consolidated financial statements and measures its pension and postretirement benefit plan assets and benefit obligations as of December 31. The obligation for the Company’s pension plans and postretirement benefit plans and the related annual costs of employee benefits are calculated based on several long-term assumptions, including discount rates and expected mortality for employee benefit liabilities, and rates of return on plan assets, and expected annual rates for salary increases for employee participants in the case of pension plans, and expected annual increases in the costs of medical and other health care benefits in the case of postretirement benefit obligations. See Note 19, Pensions and Other Employee Benefits
Stock-Based Compensation	Stock-Based Compensation: Compensation expense for restricted stock unit and stock option awards is generally recognized on a straight-line basis over the requisite service period for the entire award based on the grant date fair value. All of the stock options granted to employees by the Company are non-qualified stock options under U.S. income tax regulations. Compensation expense for performance units payable in L3 common stock is based on the fair value of the units at the grant date (measurement date), adjusted each reporting period for progress towards the target award, and recognized on a straight line basis over the requisite service period. Stock-based compensation expense is recognized net of estimated forfeitures.
Income Taxes	Income Taxes: Income tax accounting standards prescribe: (1) a minimum recognition threshold that an income tax benefit arising from an uncertain income tax position taken, or expected to be taken, on an income tax return is required to meet before being recognized in the financial statements and (2) the measurement of the income tax benefits recognized from such positions. The Company’s accounting policy is to classify uncertain income tax positions that are not expected to be resolved in one year as non-current income tax liabilities and to classify potential interest and penalties on uncertain income tax positions as elements of the provision for income taxes on its financial statements.
Cash and Cash Equivalents	Cash and Cash Equivalents:
Contracts in Process	Contracts in Process: The Company values its acquired contracts in process in connection with business acquisitions on the date of acquisition at contract value less the Company’s estimated costs to complete the contract and a reasonable profit allowance on the Company’s completion effort.
Inventories	Inventories:
Property, Plant and Equipment	Property, Plant and Equipment:
Goodwill and Indefinite-lived Intangible Assets	Goodwill and Indefinite-lived Intangible Assets:
Identifiable Intangible Assets	Identifiable Intangible Assets:
Derivative Financial Instruments	Derivative Financial Instruments: The Company’s U.S. and foreign businesses enter into contracts with customers, subcontractors or vendors that are denominated in currencies other than their functional currencies. To protect the functional currency equivalent cash flows associated with certain of these contracts, the Company enters into foreign currency forward contracts. The Company’s activities involving foreign currency forward contracts are designed to hedge the changes in the functional currency equivalent cash flows due to movements in foreign exchange rates compared to the functional currency. The foreign currencies hedged are primarily the U.S. dollar, the Euro, the Canadian dollar and the British pound. The Company manages exposure to counterparty non-performance credit risk by entering into foreign currency forward contracts only with major financial institutions that are expected to fully perform under the terms of such contracts. Foreign currency forward contracts are recorded in the Company’s balance sheets at fair value and are generally designated and accounted for as cash flow hedges in accordance with the accounting standards for derivative instruments and hedging activities. Gains and losses on designated foreign currency forward contracts that are highly effective in offsetting the corresponding change in the cash flows of the hedged transactions are recorded net of income taxes in accumulated other comprehensive income (loss) (accumulated OCI) and then recognized in income when the underlying hedged transaction affects income. Gains and losses on foreign currency forward contracts that do not meet hedge accounting criteria are recognized in income immediately.
Treasury Stock	Treasury Stock:
Translation of Foreign Currency and Foreign Currency Transactions	Translation of Foreign Currency and Foreign Currency Transactions:
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adoption of New Accounting Standards	Accounting Standards Issued and Not Yet Implemented: , Simplifying the Test for Goodwill Impairment 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 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.
Adjustments for New Accounting Pronouncement [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adoption of New Accounting Standards	New Accounting Standards Implemented: , Improvements to Employee Share-Based Payment Accounting In August 2016, the FASB issued ASU 2016-15 , Statement of Cash Flows — Classification of Certain Cash Receipts and Cash Payments Other accounting standard updates effective for interim and annual periods beginning after December 31, 2016 are not expected to have a material impact on the Company’s financial position, results of operations or cash flows.

Summary of Significant Accoun35

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Summary of Significant Accounting Policies [Abstract]
Changes in Company's Accrued Product Warranty Costs	The table below presents the changes in the Company’s accrued product warranty costs. Year Ended December 31, 2016 2015 (in millions) Accrued product warranty costs (1) : Balance at January 1 $ 105 $ 93 Acquisitions during this period 3 1 Accruals for product warranties issued during the period 51 59 Changes to accruals for product warranties existing before January 1 — 2 Foreign currency translation adjustments (1 ) (2 ) Settlements made during the period (49 ) (48 ) Balance at December 31 $ 109 $ 105 (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.

Acquisitions and Divestitures (

Acquisitions and Divestitures (Tables)	12 Months Ended
	Dec. 31, 2016
Net Sales and Income Before Income Taxes for L-3 MacDonald Humfrey, Micreo, Aerosim and ATM	Net sales and income before income taxes for L3 MacDonald Humfrey, Micreo, Aerosim and ATM, included in L3’s consolidated statement of operations for the year ended December 31, 2016, are presented in the table below. Year Ended December 31, 2016 (in millions) Net sales $ 37 Income before income taxes $ 7
Components of Loss of Business Divestitures, Related Sales Proceeds Received and Sales Included in Continuing Operations	The adjustments recorded by the Company related to the business divestitures are included in the loss related to business divestitures caption on the audited consolidated statements of operations and discussed below. Additionally, these adjustments, the proceeds received, and net sales included in continuing operations related to the Company’s business divestitures, are summarized in the table below. Year Ended December 31, 2015 Loss Related to Business Divestiture Proceeds Received Net Sales (in millions) MSI divestiture $ (17 ) $ 318 $ 185 BSI divestiture (4 ) 26 7 Tinsley Product Line divestiture (8 ) 4 9 Klein divestiture (2 ) 10 8 Total $ (31 ) $ 358 $ 209
Net Sales and Income Before Income Taxes for MSI, BSI, Tinsley Product Line and Klein	Net sales and income (loss) before income taxes for MSI, BSI, the Tinsley Product Line and Klein, included in L3’s consolidated statements of operations, are presented in the table below on an aggregate basis, and are included in income from continuing operations for all periods presented. Year Ended December 31, 2015 2014 (in millions) Net sales $ 209 $ 596 Income before income taxes $ — $ 27
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 years ended December 31, 2016 and 2015 assuming that the business acquisitions completed during 2016 and 2015 had occurred on January 1, 2015 and January 1, 2014, respectively. The unaudited pro forma Statements of Operations data below includes adjustment for additional amortization expense related to acquired intangible assets, depreciation and estimated reduction to interest income assuming the 2016 and 2015 acquisitions had occurred on January 1, 2015 and January 1, 2014, respectively. Year Ended December 31, 2016 2015 (in millions, except per share data) Pro forma net sales $ 10,655 $ 10,700 Pro forma income from continuing operations attributable to L3 $ 660 $ 307 Pro forma net income (loss) attributable to L3 $ 723 $ (215 ) Pro forma diluted earnings per share from continuing operations $ 8.38 $ 3.74 Pro forma diluted earnings (loss) per share $ 9.18 $ (2.63 )
NSS [Member]
Statement of Operations Data Classified as Discontinued Operations	The table below presents the statements 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. Year Ended December 31, 2016 2015 2014 (in millions) Net sales $ 86 $ 1,088 $ 1,138 Cost of sales (92 ) (1,040 ) (1,065 ) Gain related to business divestiture (1) 64 — — Goodwill impairment charges — (571 ) — Operating income (loss) from discontinued operations 58 (523 ) 73 Interest expense allocated to discontinued operations — (20 ) (20 ) Income (loss) from discontinued operations before income taxes 58 (543 ) 53 Income tax benefit (expense) 5 21 (21 ) Income (loss) from discontinued operations, net of income taxes $ 63 $ (522 ) $ 32 (1) The year ended December 31, 2016 includes a gain of $64 million (before and after income taxes) on the sale of the NSS business.
Major Classes of Assets and Liabilities Included as Discontinued Operations/Held For Sale	The major classes of assets and liabilities included in discontinued operations related to NSS are presented in the table below. December 31, 2015 (in millions) Assets Current assets $ 201 Property, plant and equipment, net 25 Goodwill (1) 390 Other assets 48 Total assets of discontinued operations $ 664 Liabilities Accounts payable, trade $ 48 Other current liabilities 78 Current liabilities 126 Long-term liabilities 94 Total liabilities of discontinued operations $ 220 (1) The goodwill balance at December 31, 2015 is based on an allocation of the goodwill attributable to the NSS reporting unit to discontinued operations based on the relative fair value of the NSS business retained by L3 and NSS business sold.

Contracts in Process (Tables)

Contracts in Process (Tables)	12 Months Ended
	Dec. 31, 2016
Contracts in Process [Abstract]
Components of Contracts in Process	In connection with contracts in process assumed by the Company in its business acquisitions, the underlying contractual customer relationships are separately recognized as identifiable intangible assets at the date of acquisition, and are discussed and presented in Note 6. December 31, 2016 2015 (in millions) Unbilled contract receivables, gross $ 2,020 $ 2,120 Unliquidated progress payments (827 ) (892 ) Unbilled contract receivables, net 1,193 1,228 Inventoried contract costs, gross 1,065 975 Unliquidated progress payments (203 ) (122 ) Inventoried contract costs, net 862 853 Total contracts in process $ 2,055 $ 2,081
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. Year Ended December 31, 2016 2015 2014 (in millions) Amounts included in inventoried contract costs at beginning of the year $ 137 $ 114 $ 121 Contract costs incurred: IRAD and B&P 308 284 270 Other G&A 839 822 804 Total 1,147 1,106 1,074 Amounts charged to cost of sales (1,111 ) (1,083 ) (1,081 ) Amounts included in inventoried contract costs at end of the year $ 173 $ 137 $ 114
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 consolidated statements of operations. Year Ended December 31, 2016 2015 2014 (in millions) Selling, general and administrative expenses $ 223 $ 261 $ 297 Research and development expenses 54 52 63 Total $ 277 $ 313 $ 360

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2016
Inventories [Abstract]
Inventories at Lower of Cost or Market	Inventories at Lower of Cost or Market. December 31, 2016 2015 (in millions) Raw materials, components and sub-assemblies $ 165 $ 164 Work in process 106 103 Finished goods 59 66 Total $ 330 $ 333

Goodwill and Identifiable Int39

Goodwill and Identifiable Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2016
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 Consolidated Total (in millions) Balance at December 31, 2014 Goodwill $ 3,816 $ 1,730 $ 1,024 $ 6,570 Accumulated impairment losses (43 ) — (15 ) (58 ) 3,773 1,730 1,009 6,512 Business acquisitions (1) 233 — 11 244 Business divestitures (2) (20 ) — — (20 ) Business retained from NSS divestiture 26 — 2 28 Goodwill impairment charges (26 ) (338 ) (20 ) (384 ) Foreign currency translation adjustments (3) (61 ) (39 ) 1 (99 ) Balance at December 31, 2015 Goodwill 3,994 1,691 1,038 6,723 Accumulated impairment losses (4) (69 ) (338 ) (35 ) (442 ) 3,925 1,353 1,003 6,281 Business acquisitions (1) 315 — 20 335 Foreign currency translation adjustments (3) (63 ) 7 — (56 ) Balance at December 31, 2016 Goodwill 4,246 1,698 1,058 7,002 Accumulated impairment losses (69 ) (338 ) (35 ) (442 ) $ 4,177 $ 1,360 $ 1,023 $ 6,560 (1) For the year ended December 31, 2016, the net increase in goodwill for the Electronic Systems segment was due to the L3 MacDonald Humfrey, Aeroism and Micreo business acquisitions, as well as the final purchase price allocations for the L3 ForceX and L3 CTC business acquisitions. The increase in goodwill for the Communication Systems segment was due to the ATM business acquisition. For the year ended December 31, 2015, the net increase in goodwill for the Electronic Systems segment was due to the L3 CTC and L3 ForceX business acquisitions. The increase in goodwill for the Communication Systems segment was due to the Miteq business acquisition. (2) For the year ended December 31, 2015, the decrease in goodwill for the Electronic Systems segment was due to the divestitures of BSI, the Tinsley Product Line and Klein. (3) During 2016, the decrease in goodwill presented in the Electronic Systems segment was due to the strengthening of the U.S. dollar against the British pound, the Euro and the Australian dollar, offset by the weakening of the U.S. dollar against the Canadian dollar. The increase in goodwill presented in the Aerospace Systems segment was due to the weakening of the U.S. dollar against the Canadian dollar. During 2015, the decrease in goodwil presented in the Electronic Systems segment was primarily due to the strengthening of the U.S. dollar against the Canadian dollar, the British pound and the Euro. The decrease in goodwill presented in the Aerospace Systems segment was due to the strengthening of the U.S. dollar against the Canadian dollar. (4) The accumulated impairment losses at December 31, 2015 exclude $571 million of impairment charges recorded during 2015 relating to the NSS reporting unit, which is reported in discontinued operations.
Adjustments Related to Goodwill Impairment Charges	The adjustments the Company recorded related to goodwill impairment charges are presented in a separate caption on the audited consolidated statements of operations and are summarized below. Year Ended December 31, 2015 Goodwill Impairment Charges Continuing Operations Discontinued Operations L3 Consolidated (in millions) Vertex Aerospace reporting unit impairment $ 338 $ — $ 338 NSS reporting unit impairment 37 571 608 Re-allocation of goodwill for business retained from NSS 9 — 9 Total $ 384 $ 571 $ 955
Identifiable Intangible Assets	Information on the Company’s identifiable intangible assets that are subject to amortization is presented in the table below. December 31, 2016 December 31, 2015 Weighed 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 $ 409 $ 269 $ 140 $ 370 $ 246 $ 124 Technology 11 191 102 89 156 91 65 Other 18 21 12 9 21 11 10 Total 14 $ 621 $ 383 $ 238 $ 547 $ 348 $ 199
Amortization Expense	Amortization expense recorded by the Company for its identifiable intangible assets is presented in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Amortization expense $ 35 $ 35 $ 39
Estimated Amortization Expense	Based on gross carrying amounts at December 31, 2016, 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 million s ) Estimated amortization expense $ 39 $ 35 $ 32 $ 28 $ 24

Other Current Liabilities and40

Other Current Liabilities and Other Liabilities (Tables)	12 Months Ended
	Dec. 31, 2016
Other Current Liabilities and Other Liabilities [Abstract]
Other Current Liabilities	The table below presents the components of other current liabilities. December 31, 2016 2015 (in millions) Other Current Liabilities: Estimated costs in excess of estimated contract value to complete contracts in process in a loss position $ 70 $ 75 Accrued product warranty costs 68 70 Accruals for pending and threatened litigation (see Note 18) (1) 51 6 Accrued interest 43 45 Deferred revenues 34 32 Product returns allowance (2) 5 20 Other 160 146 Total other current liabilities $ 431 $ 394 (1) The year ended December 31, 2016, includes $14 million accrued in the third quarter of 2016 in connection with the EoTech matter. (2) In November 2015, the Company commenced a voluntary return program and began accepting customer returns for various EoTech HWS products that may have been affected by certain performance issues. The return program gives eligible owners of such HWS products the option to return their products in exchange for a refund of the purchase price, including shipping costs. The Company initially recorded a reduction to net sales of $20 million in the Warrior Systems sector of the Electronic Systems segment in the fourth quarter of 2015 associated with establishing a product returns allowance to reflect the estimated cost of the return program. Beginning in the first quarter of 2016, with the benefit of a larger volume of actual refund transactions, the Company began using a statistical analysis of the voluntary return program to estimate the number and cost of future refunds. In its statistical analysis, the Company utilized empirical models to forecast the expected emergence pattern of new refunds over time to produce a probabilistic distribution of new refund costs that reflects the existing level of estimation uncertainty. Based on this analysis, the Company expects the total cost of the voluntary return program to be approximately $38 million. Accordingly, during 2016 the product returns allowance was increased by $18 million as a reduction to net sales. The product returns allowance, net of refund payments made to eligible owners, was $5 million at December 31, 2016. As of February 3, 2017, the Company had approved refunds at a cost of approximately $35 million, with an average refund cost per unit of $500. The Company will continue to monitor the product returns allowance. The Company’s ongoing evaluation may cause it to record further adjustments to the allowance in future periods. These adjustments could be material.
Other Liabilities	The table below presents the components of other liabilities. December 31, 2016 2015 (in millions) Other Liabilities: Non-current income taxes payable (see Note 16) $ 124 $ 161 Deferred compensation 47 45 Accrued product warranty costs 41 35 Accrued workers’ compensation 30 38 Estimated contingent purchase price payable for acquired businesses (see Note 3) 29 — Notes payable and capital lease obligations 13 10 Other 84 79 Total other liabilities $ 368 $ 368

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	The table below presents the components of Property, Plant and Equipment. December 31, 2016 2015 (in millions) Land $ 54 $ 60 Buildings and improvements 438 431 Machinery, equipment, furniture and fixtures 1,890 1,736 Leasehold improvements 344 343 Gross property, plant and equipment 2,726 2,570 Accumulated depreciation and amortization (1,605 ) (1,473 ) Property, plant and equipment, net $ 1,121 $ 1,097

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2016
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 current and long-term debt are presented in the table below. December 31, 2016 2015 (in millions) Borrowings under Revolving Credit Facility (1) $ — $ — 3.95% Senior Notes due 2016 — 500 1.50% Senior Notes due 2017 — 350 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 — Principal amount of long-term debt 3,350 3,650 Unamortized discounts (8 ) (8 ) Deferred debt issue costs (17 ) (16 ) Carrying amount of long-term debt 3,325 3,626 Current portion of long-term debt — (499 ) Carrying amount of long-term debt, excluding current portion $ 3,325 $ 3,127 (1) During 2016, L3's aggregate borrowings and repayments under the Credit Facility were $819 million. L3 had the full availability of its $1 billion Credit Facility at December 31, 2016 and December 31, 2015.
Information Regarding Outstanding Senior Subordinated Notes	The Senior Notes are unsecured senior obligations of L3. The terms of each outstanding Senior Note are presented in the table below. Note Date of Issuance Amount Issued Discount (1) Net Cash Proceeds Effective Interest Rate Redemption at Treasury Rate (2)(3) (in millions) 5.20% Senior Notes due October 2, 2009 $ 1,000 $ 4 $ 987 5.25 % 30 bps 4.75% Senior Notes due May 21, 2010 $ 800 $ 3 $ 790 4.79 % 25 bps 4.95% Senior Notes due February 7, 2011 $ 650 $ 4 $ 639 5.02 % 25 bps 3.95% Senior Notes due May 28, 2014 $ 650 $ 3 $ 641 (4) 4.02 % 20 bps 3.85% Senior Notes due December 5, 2016 $ 550 $ 3 $ 542 3.91 % 25 bps (1) Bond discounts are recorded as a reduction to the principal amount of the notes and are amortized as interest expense over the term of the notes. (2) The Senior Notes maturing in 2019, 2020 and 2021 may be redeemed at any time prior to their maturity and the Senior Notes maturing in 2024 and 2026 may be redeemed at any time prior to February 28, 2024 and September 15, 2026, respectively, (three months prior to their maturity) at the option of L3, in whole or in part, at a redemption price equal to the greater of: (1) 100% of the principal amount, or (2) the present value of the remaining principal and interest payments discounted to the date of redemption, on a semi-annual basis, at the Treasury Rate (as defined in the indentures governing the Senior Notes), plus the spread indicated in the table above. In addition, if the Senior Notes maturing in 2024 and 2026 are redeemed at any time on or after February 28, 2024 and September 15, 2026, respectively, the redemption price would be equal to 100% of the principal amount. (3) Upon the occurrence of a change in control (as defined in the indentures governing the Senior Notes), each holder of the notes will have the right to require L3 to repurchase all or any part of such holder’s notes at an offer price in cash equal to 101% of the aggregate principal amount plus accrued and unpaid interest, if any, to the date of purchase. (4) The net cash proceeds of $988 million (after deduction of the bond discount, underwriting expenses and commissions and other related expenses) were used primarily to fund the CODES retirement as discussed below. The remaining net proceeds were used for general corporate purposes.
Repurchases, Redemptions and Maturities of Senior Notes	The repurchases, redemptions and maturities of senior notes are presented in the table below. Note Settlement Type Date Settled Aggregate Amount Debt Retirement Charge Cash Payments (in millions) 1.50% Senior Notes due 2017 (1) Redemption December 30, 2016 $ 350 $ 2 $ 351 3.95% Senior Notes due 2016 Maturity November 15, 2016 $ 200 $ — $ 200 3.95% Senior Notes due 2016 (2) Redemption May 20, 2016 $ 300 $ 5 $ 305 3.95% Senior Notes due 2024 Tender Offer December 22, 2015 $ 300 $ 1 $ 297 CODES due 2035 (3) Redemption June 20, 2014 $ 689 $ — $ 935 (1) The 1.50% Senior Notes due 2017 were redeemed at a price equal to 100.323% of the principal amount thereof , plus accrued and unpaid interest to the redemption date. Interest ceased to accrue on and after the redemption date. (2) The 3.95% Senior Notes due 2016 were redeemed at a price equal to 101.475% of the principal amount thereof, plus accrued and unpaid interest. Interest ceased to accrue on and after May 20, 2016 and the only remaining right of holders of such Notes was to receive payment of the Redemption Price and accrued interest. (3) In 2005, L3 sold $700 million of 3% Convertible Contingent Debt Securities (CODES) due August 1, 2035. On February 2, 2011, L3 reporchased approximately $11 million of the CODES. The conversion value of CODES of $935 million was calculated in accordance with the indenture governing the CODES. L3 settled the entire conversion value with respect to converted CODES in cash. As a result of the conversion, the Company recorded a reduction to shareholders’ equity of $161 million, related to the excess conversion value over the fair value of the debt component of the CODES, net of deferred tax liability. Interest expense recognized for the CODES was $2 million for the year ended December 31, 2014.

Accumulated Other Comprehensi43

Accumulated Other Comprehensive (Loss) Income (AOCI) (Tables)	12 Months Ended
	Dec. 31, 2016
Accumulated Other Comprehensive (Loss) Income (AOCI) [Abstract]
Summary of 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, 2013 $ 142 $ 1 $ (253 ) $ (110 ) Other comprehensive loss before reclassifications, net of tax (123 ) (13 ) (354 ) (490 ) Amounts reclassified from AOCI, net of tax — 7 9 16 Net current period other comprehensive (loss) (123 ) (6 ) (345 ) (474 ) Balance at December 31, 2014 $ 19 $ (5 ) $ (598 ) $ (584 ) Other comprehensive (loss) income before reclassifications, net of tax (161 ) (15 ) 81 (95 ) Amounts reclassified from AOCI, net of tax 41 12 52 105 Net current period other comprehensive (loss) income (120 ) (3 ) 133 10 Balance at December 31, 2015 $ (101 ) $ (8 ) $ (465 ) $ (574 ) Other comprehensive (loss) income before reclassifications, net of tax (77 ) 3 (119 ) (193 ) Amounts reclassified from AOCI, net of tax — 11 30 41 Net current period other comprehensive (loss) income (77 ) 14 (89 ) (152 ) Balance at December 31, 2016 $ (178 ) $ 6 $ (554 ) $ (726 ) 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 Audited Consolidated Statements of Operations Year Ended December 31, Details About AOCI Components 2016 2015 2014 (in millions) Foreign currency translation adjustments: MSI divestiture $ — $ (41 ) $ — Loss related to business divestitures — (41 ) — Income from continuing operations before income taxes $ — $ (41 ) $ — Income from continuing operations Loss on hedging instruments: MSI divestiture $ — $ (2 ) $ — Loss related to business divestitures Other (13 ) (16 ) (8 ) Cost of sales-products (13 ) (18 ) (8 ) Income from continuing operations before income taxes 2 6 1 Provision for income taxes $ (11 ) $ (12 ) $ (7 ) Income from continuing operations Amortization of defined benefit pension items: MSI divestiture $ — $ (14 ) $ — Loss related to business divestitures Net loss (48 ) (67 ) (15 ) (b) (48 ) (81 ) (15 ) Income from continuing operations before income taxes 18 29 6 Provision for income taxes $ (30 ) $ (52 ) $ (9 ) Income from continuing operations Total reclassification for the period $ (41 ) $ (105 ) $ (16 ) Income from continuing operations (a) Amounts in parentheses indicate charges to the 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).

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [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. December 31, 2016 2015 Description Level 1 (1) Level 2 (2) Level 3 (3) Level 1 (1) Level 2 (2) Level 3 (3) (in millions) Assets Cash equivalents $ 104 $ — $ — $ 187 $ — $ — Derivatives (foreign currency forward contracts) — 12 — — 2 — Total assets $ 104 $ 12 $ — $ 187 $ 2 $ — Liabilities Derivatives (foreign currency forward contracts) $ — $ 6 $ — $ — $ 16 $ — Contingent consideration (4) — — 29 — — — Total liabilities $ — $ 6 $ 29 $ — $ 16 $ — (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 L3 MacDonald Humfrey acquisition. The fair value of the contingent consideration liability is based on a Monte Carlo Simulation of the aggregate revenue of L3 MacDonald Humfrey 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 L3 MacDonald Humfrey 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.

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2016
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. December 31, 2016 December 31, 2015 Carrying Amount Estimated Fair Value Carrying Amount Estimated Fair Value (in millions) Senior Notes (1) $ 3,325 $ 3,526 $ 3,626 $ 3,754 Foreign currency forward contracts (2) $ 6 $ 6 $ (14 ) $ (14 ) (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 14 for additional disclosures regarding the notional amounts and fair values of foreign currency forward contracts.

Derivative Financial Instrume46

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2016
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 December 31, 2016. Currency Notional Amount (in millions) U.S. dollar $ 117 Euro 109 Canadian dollar 96 British pound 28 Other 8 Total $ 358
Location of Company's Derivative Instruments Recorded at Fair Value on the Consolidated Balance Sheets	The table below presents the location of the Company’s derivative instruments recorded at fair value on the consolidated balance sheets. December 31, 2016 December 31, 2015 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) $ 10 $ 2 $ 6 $ — $ 1 $ 1 $ 15 $ 1 Total derivative instruments $ 10 $ 2 $ 6 $ — $ 1 $ 1 $ 15 $ 1 (1) See Note 12 for a description of the fair value hierarchy related to the Company's foreign currency forward contracts.

L3's Earnings Per Share (Tables

L3's Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2016
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. Year Ended December 31, 2016 2015 2014 (in millions, except per share data) Reconciliation of net income (loss): Net income (loss) $ 724 $ (225 ) $ 677 Net income from continuing operations attributable to noncontrolling interests (14 ) (15 ) (13 ) Net income (loss) attributable to L3’s common shareholders $ 710 $ (240 ) $ 664 Earnings (loss) attributable to L3’s common shareholders: Continuing operations $ 647 $ 282 $ 632 Discontinued operations, net of income tax 63 (522 ) 32 Net income (loss) attributable to L3’s common shareholders $ 710 $ (240 ) $ 664 Earnings (loss) per share attributable to L3’s common shareholders: Basic: Weighted average common shares outstanding 77.4 80.7 85.4 Basic earnings (loss) per share: Continuing operations $ 8.36 $ 3.49 $ 7.40 Discontinued operations, net of income tax 0.81 (6.46 ) 0.38 Net income (loss) $ 9.17 $ (2.97 ) $ 7.78 Diluted: Common and potential common shares: Weighted average common shares outstanding 77.4 80.7 85.4 Assumed exercise of stock options 2.6 2.4 3.0 Unvested restricted stock awards 1.0 1.3 1.6 Employee stock purchase plan contributions 0.1 0.1 — Performance unit awards 0.1 0.1 0.1 Assumed purchase of common shares for treasury (2.4 ) (2.7 ) (3.1 ) Assumed conversion of the CODES (1) — — 0.8 Common and potential common shares 78.8 81.9 87.8 Diluted earnings (loss) per share: Continuing operations $ 8.21 $ 3.44 $ 7.20 Discontinued operations, net of income tax 0.80 (6.37 ) 0.36 Net income (loss) $ 9.01 $ (2.93 ) $ 7.56 (1) The CODES were retired on June 20, 2014 and were dilutive for the year ended December 31, 2014 as the average market price of L3’s common stock during the period that the CODES were outstanding was greater than the price at which the CODES would have been convertible into L3’s common stock. As of June 18, 2014, the final date of conversion, the conversion price was $88.71.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Taxes [Abstract]
Income from Continuing Operations Before Income Taxes	Income from continuing operations before income taxes is summarized in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Domestic $ 654 $ 192 $ 707 Foreign 196 130 165 Income from continuing operations before income taxes $ 850 $ 322 $ 872
Components of Current and Deferred Portions of Provision for Income Taxes on Continuing Operations	The components of the Company’s current and deferred portions of the provision for income taxes on continuing operations are presented in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Current income tax provision: Federal $ 88 $ 60 $ 78 State and local 10 5 1 Foreign 48 26 35 Subtotal 146 91 114 Deferred income tax provision/(benefit): Federal 37 (67 ) 101 State and local 6 (1 ) 11 Foreign — 2 1 Subtotal 43 (66 ) 113 Total provision for income taxes $ 189 $ 25 $ 227
Reconciliation of Statutory Federal Income Tax Rate to Effective Income Tax Rate on Continuing Operations	A reconciliation of the statutory federal income tax rate to the effective income tax rate on continuing operations of the Company is presented in the table below. Year Ended December 31, 2016 2015 2014 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % State and local income taxes, net of federal income tax benefit 2.3 2.0 2.1 Foreign income taxes (2.9 ) (14.2 ) (3.6 ) Manufacturing benefits (2.2 ) (3.7 ) (1.7 ) Research and experimentation and other tax credits (4.4 ) (12.9 ) (4.3 ) Resolution of tax contingencies (2.9 ) (2.8 ) (1.0 ) Tax deductible dividends (0.9 ) (2.3 ) (0.8 ) Equity compensation - excess income tax benefits (2.0 ) — — Goodwill impairment — 6.6 — Other, net 0.2 0.1 0.3 Effective income tax rate on continuing operations 22.2 % 7.8 % (1) 26.0 % (1) In 2015, the Company recorded non-cash goodwill impairment charges of $384 million, which resulted in a deferred tax benefit of $120 million. Excluding the goodwill impairment charge and the related deferred income tax benefit, the effective income tax rate for 2015 would have been 20.5%.
Components of Net Deferred Tax Assets and Liabilities	The significant components of the Company’s net deferred tax assets and liabilities are presented in the table below. December 31, 2016 2015 (in millions) Deferred tax assets: Inventoried costs $ 63 $ 56 Compensation and benefits 152 147 Pension and postretirement benefits 415 354 Loss carryforwards 18 12 Tax credit carryforwards 6 6 Other 89 79 Deferred tax assets 743 654 Less: valuation allowance (12 ) (9 ) Deferred tax assets, net of valuation allowance 731 645 Deferred tax liabilities: Goodwill and other intangible assets $ (752 ) $ (675 ) Income recognition on contracts in process (63 ) (36 ) Property, plant and equipment (96 ) (94 ) Other (54 ) (56 ) Deferred tax liabilities (965 ) (861 ) Total deferred tax liabilities, net of valuation allowance $ (234 ) $ (216 )
Classification of Deferred Tax Assets and Liabilities	The classification of the Company’s deferred tax assets and liabilities are presented in the table below. December 31, 2016 2015 (in millions) Non-current deferred tax assets $ 2 $ 3 Non-current deferred tax liabilities (236 ) (219 ) Total net deferred tax liabilities $ (234 ) $ (216 )
Summary of Loss and Tax Credit Carryforwards	The Company has established a valuation allowance as indicated in those instances in which it does not believe that it is more likely than not it will generate sufficient taxable income, of the appropriate character and in the applicable subsidiary, to utilize the carryforwards. Year Ended December 31, 2016 Carryforwards Valuation Allowances Gross Tax Effected Gross Tax Effected Expiration Periods (in millions) (in millions) Capital loss carryforwards $ 6 $ 2 $ 6 $ 2 2017-2021 Federal net operating loss carryforwards 33 11 5 2 2026-2035 Foreign net operating loss carryforwards 14 3 3 1 Indefinite State net operating loss carryforwards 136 2 47 1 2017-2036 Total loss carryforwards $ 18 $ 6 State tax credit carryforwards 7 5 7 4 2017-2031 Foreign tax credit carryforwards 1 1 — — Indefinite Total tax credit carryforwards $ 6 $ 4
Reconciliation of Change in Unrecognized Income Tax Benefits, Excluding Interest and Penalties	A reconciliation of the change in unrecognized income tax benefits, excluding potential interest and penalties, is presented in the table below. 2016 2015 2014 (in millions) Balance at January 1 $ 140 $ 169 $ 155 Additions for tax positions related to the current year 16 14 20 Additions for tax positions related to prior years 2 2 12 Reductions for tax positions related to prior years (39 ) (37 ) (11 ) Reductions for tax positions related to settlements with taxing authorities (1 ) (1 ) (1 ) Reduction for tax positions related to prior years as a result of a lapse of statute of limitations (7 ) (7 ) (6 ) Balance at December 31 $ 111 $ 140 $ 169

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2016
Stock-Based Compensation [Abstract]
Stock-Based Compensation by Form of Award	The Company’s stock-based compensation by form of award, including stock-based compensation recorded in discontinued operations relating to the NSS business, is presented in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Stock options $ 10 $ 9 $ 9 Restricted stock units 35 38 40 Performance units 4 2 3 Total before income taxes 49 49 52 Income taxes (18 ) (18 ) (20 ) Total after income taxes 31 31 32 Less: Stock-based compensation recorded in discontinued operations, net of income taxes 1 (1) 1 1 Stock-based compensation recorded in continuing operations, net of income taxes $ 30 $ 30 $ 31 (1) Amount relates to the net impact of share based payment award modification in connection with the sale of NSS, which is further discussed below.
Company's Stock Option Activity and Changes	The table below presents a summary of the Company’s stock option activity at December 31, 2016 and changes during the year then ended. Number of Options Weighted Average Exercise Price Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (in thousands) (in years) (in millions) Number of shares under option: Outstanding at January 1, 2016 2,931.5 $ 92.59 6.0 $ 84 Options granted 617.6 116.68 Options exercised (647.5 ) 82.78 Options forfeited (54.1 ) 118.82 Outstanding at December 31, 2016 2,847.5 $ 99.54 6.1 $ 150 Vested and expected to vest at December 31, 2016 (1) 2,835.7 $ 99.46 6.1 $ 149 Exercisable at December 31, 2016 1,802.0 $ 87.77 4.9 $ 116 (1) Represents outstanding options reduced by expected forfeitures for options not fully vested.
Weighted Average Assumptions in Valuation Model	Changes in assumptions can materially impact the estimated fair value of stock options. The weighted average assumptions used in the valuation model are presented in the table below. 2016 Grants 2015 Grants 2014 Grants Expected holding period (in years) 5.0 5.0 5.5 Expected volatility 21.3 % 21.4 % 24.4 % Expected dividend yield 2.8 % 2.4 % 2.7 % Risk-free interest rate 1.1 % 1.5 % 1.7 %
Company's Nonvested Restricted Stock Unit Awards and Changes	The table below presents a summary of the Company’s nonvested restricted stock unit awards at December 31, 2016 and changes during the year then ended. Number of Shares Weighted Average Grant Date Fair Value (in thousands) Nonvested balance at January 1, 2016 1,171.9 $ 102.91 Granted 397.6 116.72 Vested (478.3 ) 76.83 Forfeited (113.3 ) 111.89 Nonvested balance at December 31, 2016 977.9 $ 120.24
Company's Performance Unit Awards Based on Expected Performance	The table below presents a summary of the Company’s performance unit awards based on expected performance at December 31, 2016 and changes during the year then ended. Payable in Shares (EPS) Number of Units Weighted Average Grant Date Fair Value (in thousands) Outstanding at January 1, 2016 39.6 $ 121.27 Granted 51.9 116.20 Increase due to expected performance 35.6 127.14 Vested — — Forfeited (2.4 ) 121.72 Outstanding at December 31, 2016 124.7 $ 120.83

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies [Abstract]
Future Minimum Payments under Non-Cancelable Operating Leases	The following table presents future minimum payments under non-cancelable operating leases with initial or remaining terms in excess of one year at December 31, 2016. Real Estate Equipment Total (in millions) 2017 $ 94 $ 5 $ 99 2018 81 3 84 2019 63 2 65 2020 90 — 90 2021 45 — 45 Thereafter 213 — 213 Total minimum payments required 586 10 596 Less: Sublease rentals under non-cancelable leases 10 — 10 Net minimum payments required $ 576 $ 10 $ 586

Pensions and Other Employee B51

Pensions and Other Employee Benefits (Tables)	12 Months Ended
	Dec. 31, 2016
Pensions and Other Employee Benefits [Abstract]
Changes in Benefit Obligations, Plan Assets and Funded Status and Aggregate Balance Sheet Impact	The following table summarizes changes in the benefit obligations, the plan assets and funded status for all of the Company’s pension and postretirement benefit plans, as well as the aggregate balance sheet impact. Pension Plans Postretirement Benefit Plans 2016 2015 2016 2015 (in millions) Change in benefit obligation: Benefit obligation at the beginning of the year $ 3,448 $ 3,663 $ 184 $ 199 Service cost 108 123 2 3 Interest cost 135 149 6 7 Plan participants’ contributions 2 2 4 4 Amendments 15 — (3 ) — Actuarial loss (gain) 167 (261 ) (3 ) (12 ) Foreign currency exchange rate changes 9 (53 ) — (4 ) Curtailments, settlements and special termination benefits 2 3 — — Business divestiture — (59 ) — — Benefits paid (128 ) (119 ) (13 ) (13 ) Benefit obligation at the end of the year $ 3,758 $ 3,448 $ 177 $ 184 Change in plan assets: Fair value of plan assets at the beginning of the year $ 2,552 $ 2,570 $ 57 $ 60 Actual return on plan assets 189 54 5 — Employer contributions 97 97 7 6 Plan participants’ contributions 2 2 4 4 Foreign currency exchange rate changes 9 (52 ) — — Benefits paid (128 ) (119 ) (13 ) (13 ) Fair value of plan assets at the end of the year $ 2,721 $ 2,552 $ 60 $ 57 Unfunded status at the end of the year $ (1,037 ) $ (896 ) $ (117 ) $ (127 ) Assets and (liabilities) recognized on the consolidated balance sheets consist of: Non-current assets $ 37 $ 37 $ — $ — Current liabilities (6 ) (5 ) (8 ) (8 ) Non-current liabilities (1,068 ) (928 ) (109 ) (119 ) $ (1,037 ) $ (896 ) $ (117 ) $ (127 )
Net Loss and Prior Service Cost Balances in Accumulated Other Comprehensive Loss Account	The table below summarizes the net loss and prior service cost balances at December 31, in the accumulated other comprehensive loss account, before related tax effects, for all of the Company’s pension and postretirement benefit plans. Pension Plans Postretirement Benefit Plans 2016 2015 2016 2015 (in millions) Net loss (gain) $ 896 $ 768 $ (12 ) $ (10 ) Prior service cost (credit) 14 — (4 ) (3 ) Total amount recognized $ 910 $ 768 $ (16 ) $ (13 )
Pension Plans with an Accumulated Benefit Obligation in Excess of Fair Value of Plan Assets	The aggregate accumulated benefit obligation (ABO) for all of the Company’s pension plans was $3,413 million at December 31, 2016 and $3,120 million at December 31, 2015. The table below presents information for the pension plans with an ABO in excess of the fair value of plan assets at December 31, 2016 and 2015. Pension Plans 2016 2015 (in millions) Projected benefit obligation $ 3,528 $ 3,232 Accumulated benefit obligation $ 3,192 $ 2,913 Fair value of plan assets $ 2,456 $ 2,302
Weighted Average Assumptions Used to Determine Benefit Obligations	The table below summarizes the weighted average assumptions used to determine the benefit obligations for the Company’s pension and postretirement plans disclosed at December 31, 2016 and 2015. Pension Plans Postretirement Benefit Plans 2016 2015 2016 2015 Benefit obligations: Discount rate 4.41 % (1) 4.67 % (1) 4.05 % (2) 4.22 % (2) Rate of compensation increase 3.50 % (3) 3.50 % (3) (1) The weighted average discount rate assumptions used at December 31, 2016 and 2015 were comprised of separate assumptions determined by country of 4.46% and 4.73% for the U.S. based plans, respectively, and 3.80% and 3.93% for the Canadian based plans, respectively. (2) The weighted average discount rate assumptions used at December 31, 2016 and 2015 were comprised of separate assumptions determined by country of 4.11% and 4.28% for the U.S. based plans, respectively, and 3.64% and 3.74% for the Canadian based plans, respectively. (3) The weighted average rate of compensation increase assumptions were comprised of separate assumptions determined by country of 3.5% for both the U.S. based plans and Canadian based plans at December 31, 2016 and 2015.
Components of Net Periodic Benefit Cost	The following table summarizes the components of net periodic benefit cost for the Company’s pension and postretirement benefit plans for the years ended December 31, 2016, 2015 and 2014. Pension Plans Postretirement Benefit Plans 2016 2015 2014 2016 2015 2014 (in millions) Components of net periodic benefit cost: Service cost $ 108 $ 123 $ 106 $ 2 $ 3 $ 3 Interest cost 135 149 147 6 7 8 Expected return on plan assets (200 ) (205 ) (193 ) (4 ) (5 ) (4 ) Amortization of prior service cost (credits) — 1 2 (2 ) (2 ) (2 ) Amortization of net loss (gain) 52 68 17 (2 ) — (2 ) Curtailment or settlement loss (gain) 2 3 1 — — (1 ) Net periodic benefit cost $ 97 $ 139 $ 80 $ — $ 3 $ 2
Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income	The following table summarizes the other changes in plan assets and benefit obligations recognized in other comprehensive income for the Company’s pension and postretirement benefit plans for the years ended December 31, 2016, 2015 and 2014. Pension Plans Postretirement Benefit Plans 2016 2015 2014 2016 2015 2014 (in millions) Other changes in plan assets and benefit obligations recognized in other comprehensive income: Net loss (gain) $ 179 $ (132 ) $ 560 $ (4 ) $ (7 ) $ 5 Prior service cost (credit) 15 — 1 (2 ) — (1 ) Amortization of net (loss) gain (52 ) (68 ) (17 ) 2 — 2 Amortization of prior service (cost) credit — (1 ) (2 ) 2 2 2 Total recognized in other comprehensive income 142 (201 ) 542 (2 ) (5 ) 8 Total recognized in net periodic benefit cost and other comprehensive income $ 239 $ (62 ) $ 622 $ (2 ) $ (2 ) $ 10
Amounts Expected to be Amortized from Accumulated OCI and Recognized as Components of Net Periodic Benefit Costs	The following table summarizes the amounts expected to be amortized from accumulated OCI and recognized as components of net periodic benefit costs during 2017. Pension Plans Postretirement Benefit Plans Total (in millions) Net loss (gain) $ 62 $ (2 ) $ 60 Prior service cost (credit) 1 (1 ) — $ 63 $ (3 ) $ 60
Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost	The table below summarizes the weighted average assumptions used to determine the net periodic benefit cost for the years ended December 31, 2016, 2015 and 2014. Pension Plans Postretirement Benefit Plans 2016 2015 2014 2016 2015 2014 Discount rates: Benefit obligation 4.67 % (1) 4.14 % (1) 5.03 % (1) 4.22 % (4) 3.70 % (4) 4.43 % (4) Service cost 4.83 % — (5) — (5) 4.37 % — (5) — (5) Interest cost 3.95 % — (5) — (5) 3.26 % — (5) — (5) Expected long-term return on plan assets 7.92 % (2) 8.14 % (2) 8.13 % (2) 7.42 % 7.65 % 7.64 % Rate of compensation increase 3.50 % (3) 3.50 % (3) 3.50 % (3) (1) The weighted average discount rate assumptions used for the years ended December 31, 2016, 2015, and 2014 were comprised of separate assumptions determined by country of 4.73%, 4.20% and 5.10% for the U.S. based plans and 3.93%, 3.90% and 4.70% for the Canadian based plans, respectively. (2) The weighted average expected long-term return on plan assets assumptions used were comprised of separate assumptions determined by country of 8.00% and 8.25% for the U.S. based plans for the years ended December 31, 2016 and 2015, respectively, and 7.25% for the Canadian based plans for the years ended December 31, 2016, and 2015. (3) The weighted average rate of compensation increase assumptions used for the years ended December 31, 2016, 2015 and 2014 were comprised of separate assumptions determined by country of 3.50% for both the U.S and Canadian based plans. (4) The weighted average discount rate assumptions used for the years ended December 31, 2016, 2015 and 2014 were comprised of separate assumptions determined by country of 4.28%, 3.70% and 4.40% for the U.S. based plans and 3.74%, 3.70% and 4.60% for the Canadian based plans, respectively. (5) Not applicable as the Company changed to the spot rate approach beginning in 2016 as described above.
Effect of One Percentage Point Change in Assumed Health Care Cost Trend Rates	A one percentage point change in the assumed health care cost trend rates would have the following effects: 1 percentage point Increase Decrease (in millions) Effect on total service and interest cost $ — $ — Effect on postretirement benefit obligations $ 5 $ (4 )
Allowable Range for Each Major Category of the Plans' Assets and Weighted-Average Asset Allocations by Asset Category	The table below presents the allowable range for each major category of the plans’ assets at December 31, 2016 as well as the Company’s pension plan and postretirement benefit plan weighted-average asset allocations at December 31, 2016 and 2015, by asset category. U.S. Canada Asset Category Range 2016 2015 Range 2016 2015 Domestic equity (1) 30%-60% 55 % 52 % — 15 % 13 % International equity (2) 10%-20% 10 11 — 62 62 Total equities 45%-75% 65 63 40%-80% 77 75 Fixed income securities 20%-40% 22 22 — 13 16 Other, primarily cash and cash equivalents 0%-15% 5 8 — 10 9 Total fixed income securities and cash and cash equivalents — 27 30 20%-60% 23 25 Real estate securities 0%-15% 8 7 — — — Total 100 % 100 % 100 % 100 % (1) Domestic equities for Canadian plans refers to equities of Canadian companies. (2) International equities for Canadian plans includes equities of U.S. companies.
Fair Value of the Company's Pension Plans' and Postretirement Benefit Plans' Assets	The table below presents the fair value of the Company’s pension plans’ assets by asset category segregated by level within the fair value hierarchy, as described below. U.S. Pension Plans’ Assets Canadian Pension Plans’ Assets Fair Value Measured at December 31, 2016 Fair Value Measured at December 31, 2016 Asset Category Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in millions) Equity securities (1) U.S. Equity $ 1,331 $ — $ — $ 1,331 $ 79 $ — $ — $ 79 International Equity 85 — — 85 104 — — 104 Fixed Income — Investment Grade (2) 255 159 — 414 — — — — Fixed Income — High Yield (3) — 136 — 136 — — — — Real Estate Investment Trusts (4) 193 — — 193 — — — — Other (5) — 114 — 114 5 27 — 32 Total assets at fair value $ 1,864 $ 409 $ — $ 2,273 $ 188 $ 27 $ — $ 215 Liabilities for unsettled trades, net (23 ) — Other investments measured at net asset value (6)(7) 171 85 Total $ 2,421 $ 300 U.S. Pension Plans’ Assets Canadian Pension Plans’ Assets Fair Value Measured at December 31, 2015 Fair Value Measured at December 31, 2015 Asset Category Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in millions) Equity securities (1) U.S. Equity $ 1,200 $ — $ — $ 1,200 $ 73 $ — $ — $ 73 International Equity 79 — — 79 91 — — 91 Fixed Income — Investment Grade (2) 237 163 — 400 — — — — Fixed Income — High Yield (3) — 114 — 114 — — — — Real Estate Investment Trusts (4) 170 — — 170 — — — — Other (5) — 166 — 166 6 21 — 27 Total assets at fair value $ 1,686 $ 443 $ — $ 2,129 $ 170 $ 21 $ — $ 191 Liabilities for unsettled trades, net (30 ) — Other investments measured at net asset value (6)(7) 170 92 Total $ 2,269 $ 283 (1) Equity securities consist of investments in common stock of U.S. and international companies. The fair value of equity securities is based on quoted market prices available in active markets at the close of a trading day, primarily the New York Stock Exchange (NYSE), National Association of Securities Dealers Automated Quotations (NASDAQ), and various international exchanges. (2) Approximately 62% and 59% at December 31, 2016 and 2015, respectively, of U.S. plan assets that are invested in the Fixed Income — Investment Grade asset category consist of a mutual fund offered by a registered investment company (the Fund) and fixed income securities. The Fund invests in investment grade fixed income securities, mortgaged-backed securities, U.S. treasury and agency bonds and corporate bonds. These investments are classified by the Company as a Level 1 measurement within the fair value hierarchy, as the mutual fund trades on an active market and daily, quoted prices are available. The remaining 38% and 41% at December 31, 2016 and 2015, respectively, of U.S. plan assets are fixed income securities, primarily investment grade corporate bonds from various industries held directly by the plan. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs and are classified as Level 2. (3) Fixed Income — High Yield consists of investments in corporate high-yield bonds from various industries. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs. (4) Real Estate Investment Trusts (REITs) consist of securities that trade on the major exchanges and invest directly in real estate, either through properties or mortgages. (5) Other consists primarily of: (1) money market accounts, which invest primarily in short-term, high quality money market securities such as government obligations, commercial paper, time deposits and certificates of deposit, and are classified as Level 2, and (2) cash, which is classified as Level 1. (6) In accordance with ASU 2015-07, certain investments that are measured at fair value using the net asset value (NAV) per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statements of financial position. (7) All of the U.S. plans other investments measured using NAV at December 31, 2016 and 2015 and approximately 55% and 52% at December 31, 2016 and 2015, respectively, of the Canadian plans other investments measured using NAV consist of a regulated commingled equity trust fund, for which fair value is based on the NAV at the end of each month. The NAV is calculated by the fund manager based on the fair value of the fund’s holdings, primarily equity securities traded in active markets, determined as of the end of each month as a practical expedient to estimating fair value. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Withdrawals are permitted, with notice by the 20th day of each month, based on NAV. Approximately 45% and 48% at December 31, 2016 and 2015, respectively, of the Canadian plans other investments measured using NAV are invested in regulated commingled bond funds (the “Bond Funds”). As these Bond Funds do not trade in an active market, the fair value is based on NAVs calculated by fund managers based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs as a practical expedient to estimating fair value and classified as Level 2. Withdrawals are permitted monthly, with notice between 0 and 3 days of the transaction date, based on NAV. The table below presents the fair value of the Company’s postretirement benefit plans’ assets by asset category segregated by level within the fair value hierarchy, as described below. Postretirement Benefit Plans’ Assets Fair Value Measured at December 31, 2016 Fair Value Measured at December 31, 2015 Asset Category Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total (in millions) Equity securities (1) U.S. Equity $ 37 $ — $ — $ 37 $ 35 $ — $ — $ 35 International Equity 1 — — 1 1 — — 1 Fixed Income — Investment Grade (2) 8 3 — 11 8 3 — 11 Fixed Income — High Yield (3) — 2 — 2 — 2 — 2 Real Estate Investment Trusts (4) 3 — — 3 3 — — 3 Other (5) — 3 — 3 — 2 — 2 Total assets at fair value $ 49 $ 8 $ — $ 57 $ 47 $ 7 $ — $ 54 Other investments measured at net asset value (6)(7) 3 3 Total $ 60 $ 57 (1) Equity securities consist of investments in common stock of U.S. and international companies. The fair value of equity securities is based on quoted market prices available in active markets at the close of a trading day, primarily the NYSE, NASDAQ, and various international exchanges. (2) Approximately 73% at December 31, 2016 and 2015 of the postretirement benefit plan assets that are invested in the Fixed Income — Investment Grade asset category consist of the Fund and fixed income securities. The Fund invests in investment grade fixed income securities, mortgaged-backed securities, U.S. treasury and agency bonds and corporate bonds. These investments are classified by the Company as a Level 1 measurement within the fair value hierarchy as the mutual fund trades on an active market and daily, quoted prices are available. The remaining 27% at December 31, 2016 and 2015 of the postretirement benefit plan assets are fixed income securities, primarily investment grade corporate bonds from various industries held directly by the plan. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs and are classified as Level 2. (3) Fixed Income — High Yield consists of investments in corporate high-yield bonds from various industries. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs. (4) REITs consist of securities that trade on the major exchanges and invest directly, either through properties or mortgages. (5) Other consists primarily of money market accounts, which invest primarily in short-term, high quality money market securities such as government obligations, commercial paper, time deposits and certificates of deposit. (6) In accordance with ASU 2015-07, certain investments that are measured at fair value using the NAV per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statements of financial position. (7) All of the postretirement benefit plans other investments measured using NAV at December 31, 2016 and 2015 consist of a regulated commingled equity trust fund, which fair value is based on NAV at the end of each month. The NAV is calculated by the fund manager based on the fair value of the fund’s holdings, primarily equity securities traded in active markets, determined as of the end of each month as a practical expedient to estimating fair value. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Withdrawals are permitted, with notice by the 20th day of each month, based on NAV.
Estimated Future Benefit Payments	Estimated Future Benefit Payments. Postretirement Benefits Pension Benefits Benefit Payments Subsidy Receipts (in millions) 2017 $ 162 $ 13 $ — 2018 156 13 — 2019 162 14 — 2020 171 14 — 2021 175 14 — Years 2022-2026 1,001 65 1
Cash Contributions and Expenses under Multi-Employer Benefit Plans	Under these plans, the Company contributed cash and recorded expenses for each of its individually significant plans and all of its other plans in aggregate as noted in the table below. EIN/Pension Plan Number Pension Protection Act Zone Status (1) FIP/RP (2) Status Pending/ Implemented Contributions by L3 Surcharge Imposed Expiration Date of Collective- Bargaining Agreement Pension Fund 2016 2015 2016 2015 2014 (in millions) IAM National Pension Fund 51-6031295/002 Green Green No $ 26 (3) $ 23 (4) $ 19 (4) No 4/9/2017 to (5) Other Pension Funds (6) — — — Total contributions $ 26 $ 23 $ 19 (1) A zone status rating of green indicates the plan is at least 80% funded. (2) Funding improvement plan or rehabilitation plan. (3) At the date the audited financial statements for the Company were issued, the Form 5500 for the plan year ended December 31, 2016 was not available. (4) Represents 5% of total plan contributions for the years ended December 31, 2015 and 2014 based on Form 5500. (5) The Company is a party to multiple bargaining agreements for multiple projects that require contributions into the IAM National Pension Fund. The most significant of these agreements, expiring April 28, 2019, covers multiple programs in the Company’s Aerospace Systems reportable segment and represents 63% of 2016 contributions. (6) Consists of three pension funds in which the Company’s contributions are individually, and in the aggregate, insignificant.

Supplemental Cash Flow Inform52

Supplemental Cash Flow Information (Tables)	12 Months Ended
	Dec. 31, 2016
Supplemental Cash Flow Information [Abstract]
Supplemental Cash Flow Information	Year Ended December 31, 2016 2015 2014 (in millions) Interest paid on outstanding debt $ 162 $ 182 $ 176 Income tax payments $ 120 $ 132 $ 129 Income tax refunds $ 8 $ 8 $ 9

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2016
Segment Information [Abstract]
Summary of Segment Information	The tables below present net sales, operating income (loss), depreciation and amortization, capital expenditures and total assets by reportable segment. Year Ended December 31, 2016 2015 2014 (in millions) Net Sales Products Electronic Systems $ 3,293 $ 3,390 $ 3,685 Aerospace Systems 1,662 1,661 1,722 Communication Systems 1,585 1,648 1,546 Elimination of intercompany sales (98 ) (110 ) (114 ) Total products sales 6,442 6,589 6,839 Services Electronic Systems $ 1,042 $ 999 $ 1,057 Aerospace Systems 2,580 2,503 2,604 Communication Systems 488 441 539 Elimination of intercompany sales (41 ) (66 ) (53 ) Total services sales 4,069 3,877 4,147 Consolidated total $ 10,511 $ 10,466 $ 10,986 Operating income Electronic Systems $ 518 $ 489 $ 533 Aerospace Systems 289 205 283 Communication Systems 201 196 196 Segment total 1,008 890 1,012 Loss related to business divestitures (1) — (31 ) — Goodwill impairment charges (2) — (384 ) — Consolidated total $ 1,008 $ 475 $ 1,012 Year Ended December 31, 2016 2015 2014 (in millions) Depreciation and amortization Electronic Systems $ 105 $ 110 $ 123 Aerospace Systems 54 50 40 Communication Systems 47 50 51 Consolidated total $ 206 $ 210 $ 214 Capital Expenditures Electronic Systems $ 113 $ 99 $ 80 Aerospace Systems 56 55 59 Communication Systems 37 37 29 Corporate 10 6 6 Consolidated total $ 216 $ 197 $ 174 Total Assets Electronic Systems $ 6,802 $ 6,426 $ 6,281 Aerospace Systems 2,535 2,630 3,011 Communication Systems 2,031 1,984 2,025 Corporate 497 365 566 Assets held for sale — — 547 Assets of discontinued operations — 664 1,262 Consolidated total $ 11,865 $ 12,069 $ 13,692 (1) See Note 3 for information regarding the Company’s business divestitures. (2) Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information.
Property, Plant and Equipment by Geographic Area	The table below presents property, plant and equipment, net by geographic area. Year Ended December 31, 2016 2015 (in millions) United States $ 974 $ 971 All Other 147 126 Total $ 1,121 $ 1,097
Company's Sales Attributable to U.S. Customers and International Customers	The Company’s sales attributable to U.S. and international customers, based on location of the customer, are summarized in the table below. Year Ended December 31, 2016 2015 2014 (in millions) U.S. $ 8,199 $ 7,908 $ 8,051 International: United Kingdom 331 336 335 Canada 297 281 289 Australia 254 321 254 Saudi Arabia 159 201 160 South Korea 127 207 226 Japan 81 95 124 France 75 62 74 Other 988 1,055 1,473 Total international 2,312 2,558 2,935 Consolidated $ 10,511 $ 10,466 $ 10,986
Net Sales to Principal Customers	Net sales to principal customers are summarized in the table below. Year Ended December 31, 2016 2015 2014 (in millions) U.S. Government agencies (1) $ 7,649 $ 7,291 $ 7,464 Commercial 1,282 1,376 1,656 Foreign governments (1) 1,580 1,799 1,866 Consolidated $ 10,511 $ 10,466 $ 10,986 (1) Includes sales for which the Company is the prime contractor as well as sales based on the ultimate end customer for which the Company is a subcontractor.

Employee Severance and Termin54

Employee Severance and Termination Costs (Tables)	12 Months Ended
	Dec. 31, 2016
Employee Severance and Termination Costs [Abstract]
Employee Severance and Other Termination Costs Incurred by Reportable Segment	Employee severance and other termination costs incurred by reportable segment are presented in the table below. Year Ended December 31, 2016 2015 2014 (in millions) Electronic Systems $ 8 $ 8 $ 16 Aerospace Systems 2 4 5 Communication Systems 7 6 8 Consolidated $ 17 $ 18 $ 29

Unaudited Quarterly Financial55

Unaudited Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2016
Unaudited Quarterly Financial Data [Abstract]
Unaudited Quarterly Financial Data	Unaudited summarized financial data by quarter for the years ended December 31, 2016 and 2015 is presented in the table below. The Company’s unaudited quarterly results of operations are affected, significantly in some periods, by our business acquisitions and divestitures. See Note 3. First Quarter Second Quarter Third Quarter Fourth Quarter (in millions, except per share data) 2016 Sales $ 2,353 $ 2,664 $ 2,505 $ 2,989 Operating income 252 247 215 294 Income from continuing operations 167 151 151 192 Net income 230 151 151 192 Net income attributable to L3 227 147 148 188 Basic EPS from continuing operations (1) 2.11 1.90 1.91 2.43 Basic EPS (1) 2.92 1.90 1.91 2.43 Diluted EPS from continuing operations (1) 2.08 1.88 1.88 2.38 Diluted EPS (1) 2.87 1.88 1.88 2.38 2015 Sales $ 2,488 $ 2,543 $ 2,564 $ 2,871 Operating income (loss) 187 153 231 (96 ) Income (loss) from continuing operations 105 120 128 (56 ) Net income (loss) 109 124 (296 ) (162 ) Net income (loss) attributable to L3 105 120 (299 ) (166 ) Basic earnings (loss) per share from continuing operations (1) 1.23 1.41 1.56 (0.76 ) Basic earnings (loss) per share (1) 1.28 1.46 (3.74 ) (2.11 ) Diluted earnings (loss) per share from continuing operations (1) 1.20 1.39 1.54 (0.76 ) Diluted earnings (loss) per share (1) 1.25 1.44 (3.68 ) (2.11 ) (1) EPS in each quarter is computed using the weighted-average number of shares outstanding during that quarter, while EPS for the full year is computed using the weighted-average number of shares outstanding during the year. Therefore, the sum of the four quarters’ EPS may not equal the full year computed EPS.

Financial Information of L3 a56

Financial Information of L3 and Its Subsidiaries (Tables)	12 Months Ended
	Dec. 31, 2016
Financial Information of L3 and Its Subsidiaries [Abstract]
Condensed Combining Balance Sheets	The following 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 elimination of the holding company structure and the Merger discussed in Note 2, prior year amounts have been recast to conform to the current year presentation. L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) Condensed Combining Balance Sheets: 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 2,162 3,227 1,171 — 6,560 Other assets 705 591 312 — 1,608 Investment in and amounts due from consolidated subsidiaries 5,867 5,430 — (11,297 ) — Total assets $ 10,216 $ 10,846 $ 2,236 $ (11,433 ) $ 11,865 Current liabilities $ 789 $ 1,022 $ 460 $ (136 ) $ 2,135 Amounts due to consolidated subsidiaries — — 282 (282 ) — Other long-term liabilities 1,549 200 32 — 1,781 Long-term debt 3,325 — — — 3,325 Total liabilities 5,663 1,222 774 (418 ) 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 $ 2,236 $ (11,433 ) $ 11,865 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) At December 31, 2015: Current assets: Cash and cash equivalents $ 137 $ — $ 165 $ (95 ) $ 207 Billed receivables, net 278 297 171 — 746 Contracts in process 872 958 251 — 2,081 Other current assets 288 137 109 — 534 Assets of discontinued operations — 664 — — 664 Total current assets 1,575 2,056 696 (95 ) 4,232 Goodwill 2,318 2,973 990 — 6,281 Other assets 800 496 260 — 1,556 Investment in and amounts due from consolidated subsidiaries 5,609 3,739 111 (9,459 ) — Total assets $ 10,302 $ 9,264 $ 2,057 $ (9,554 ) $ 12,069 Current portion of long-term debt $ 499 $ — $ — $ — $ 499 Current liabilities 911 899 445 (95 ) 2,160 Liabilities of discontinued operations — 220 — — 220 Other long-term liabilities 1,410 195 29 — 1,634 Long-term debt 3,127 — — — 3,127 Total liabilities 5,947 1,314 474 (95 ) 7,640 L3 shareholders’ equity 4,355 7,950 1,583 (9,533 ) 4,355 Noncontrolling interests — — — 74 74 Total equity 4,355 7,950 1,583 (9,459 ) 4,429 Total liabilities and equity $ 10,302 $ 9,264 $ 2,057 $ (9,554 ) $ 12,069
Condensed Combining Statements of Operations	L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) Condensed Combining Statements of Operations: For the year ended December 31, 2016: Total net sales $ 3,388 $ 6,063 $ 1,379 $ (319 ) $ 10,511 Total cost of sales (3,078 ) (5,610 ) (1,134 ) 319 (9,503 ) Operating income 310 453 245 — 1,008 Interest expense (168 ) (1 ) — — (169 ) Interest and other income, net 11 1 6 — 18 Debt retirement charge (7 ) — — — (7 ) Income from continuing operations before income taxes 146 453 251 — 850 Provision for income taxes (32 ) (101 ) (56 ) — (189 ) Equity in net income of consolidated subsidiaries 596 — — (596 ) — Income from continuing operations 710 352 195 (596 ) 661 Income from discontinued operations, net of income tax — 63 — — 63 Net income 710 415 195 (596 ) 724 Net income attributable to noncontrolling interests — — — (14 ) (14 ) Net income attributable to L3 $ 710 $ 415 $ 195 $ (610 ) $ 710 Comprehensive income attributable to L3 $ 558 $ 425 $ 118 $ (543 ) $ 558 For the year ended December 31, 2015: Total net sales $ 3,580 $ 5,265 $ 1,935 $ (314 ) $ 10,466 Total cost of sales (3,283 ) (4,906 ) (1,701 ) 314 (9,576 ) (Loss) gain related to business divestitures (13 ) (31 ) 13 — (31 ) Goodwill impairment charges — (364 ) (20 ) — (384 ) Operating income (loss) 284 (36 ) 227 — 475 Interest expense (167 ) (1 ) (1 ) — (169 ) Interest and other income, net 16 — 1 — 17 Debt retirement charge (1 ) — — — (1 ) Income (loss) from continuing operations before income taxes 132 (37 ) 227 — 322 (Provision) benefit for income taxes (10 ) 3 (18 ) — (25 ) Equity in net loss of consolidated subsidiaries (362 ) — — 362 — (Loss) income from continuing operations (240 ) (34 ) 209 362 297 Loss from discontinued operations, net of income tax — (522 ) — — (522 ) Net (loss) income (240 ) (556 ) 209 362 (225 ) Net income attributable to noncontrolling interests — — — (15 ) (15 ) Net (loss) income attributable to L3 $ (240 ) $ (556 ) $ 209 $ 347 $ (240 ) Comprehensive (loss) income attributable to L3 $ (230 ) $ (560 ) $ 98 $ 462 $ (230 ) For the year ended December 31, 2014: Total net sales $ 3,586 $ 5,460 $ 2,218 $ (278 ) $ 10,986 Total cost of sales (3,255 ) (5,017 ) (1,980 ) 278 (9,974 ) Operating income 331 443 238 — 1,012 Interest expense (156 ) (2 ) — — (158 ) Interest and other income, net 15 — 3 — 18 Income from continuing operations before income taxes 190 441 241 — 872 Provision for income taxes (49 ) (115 ) (63 ) — (227 ) Equity in net income of consolidated subsidiaries 523 — — (523 ) — Income from continuing operations 664 326 178 (523 ) 645 Income from discontinued operations, net of income tax — 32 — — 32 Net income 664 358 178 (523 ) 677 Net income attributable to noncontrolling interests — — — (13 ) (13 ) Net income attributable to L3 $ 664 $ 358 $ 178 $ (536 ) $ 664 Comprehensive income attributable to L3 $ 190 $ 356 $ 47 $ (403 ) $ 190
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 year ended December 31, 2016: Operating activities: Net cash from operating activities from continuing operations $ 482 $ 542 $ 259 $ (186 ) $ 1,097 Investing activities: Business acquisitions, net of cash acquired (388 ) — — — (388 ) Proceeds from sale of business, net of closing date cash balances 563 — (2 ) — 561 Other investing activities (60 ) (86 ) (43 ) — (189 ) Net cash from (used in) investing activities from continuing operations 115 (86 ) (45 ) — (16 ) Financing activities: Proceeds from sale of senior notes 547 — — — 547 Redemption of senior notes (856 ) — — — (856 ) Common stock repurchased (373 ) — — — (373 ) Dividends paid on L3’s common stock (220 ) — — — (220 ) Other financing activities 459 (399 ) (159 ) 145 46 Net cash used in financing activities from continuing operations (443 ) (399 ) (159 ) 145 (856 ) Effect of foreign currency exchange rate changes on cash — — (13 ) — (13 ) Net decrease in cash and cash equivalents of discontinued operations — (56 ) — — (56 ) Net increase in cash 154 1 42 (41 ) 156 Cash and cash equivalents, beginning of the year 137 — 165 (95 ) 207 Cash and cash equivalents, end of the year $ 291 $ 1 $ 207 $ (136 ) $ 363 L3 Guarantor Subsidiaries Non- Guarantor Subsidiaries Eliminations Consolidated L3 (in millions) For the year ended December 31, 2015: Operating activities: Net cash from operating activities from continuing operations $ 616 $ 422 $ 216 $ (185 ) $ 1,069 Investing activities: Business acquisitions, net of cash acquired (320 ) — — — (320 ) Proceeds from sale of business, net of closing date cash balances 14 28 276 — 318 Other investing activities (84 ) (69 ) (37 ) — (190 ) Net cash (used in) from investing activities from continuing operations (390 ) (41 ) 239 — (192 ) Financing activities: Repurchases of senior notes (297 ) — — — (297 ) Common stock repurchased (740 ) — — — (740 ) Dividends paid on L3's common stock (214 ) — — — (214 ) Other financing activities 801 (434 ) (473 ) 152 46 Net cash used in financing activities from continuing operations (450 ) (434 ) (473 ) 152 (1,205 ) Effect of foreign currency exchange rate changes on cash — — (19 ) — (19 ) Net increase in cash and cash equivalents of discontinued operations — 51 — — 51 Change in cash balance in assets held for sale — 1 60 — 61 Net (decrease) increase in cash (224 ) (1 ) 23 (33 ) (235 ) Cash and cash equivalents, beginning of the year 361 1 142 (62 ) 442 Cash and cash equivalents, end of the year $ 137 $ — $ 165 $ (95 ) $ 207 For the year ended December 31, 2014: Operating activities: Net cash from operating activities from continuing operations $ 467 $ 571 $ 143 $ (93 ) $ 1,088 Investing activities: Business acquisitions, net of cash acquired (57 ) — — — (57 ) Other investing activities (58 ) (85 ) (21 ) — (164 ) Net cash used in investing activities from continuing operations (115 ) (85 ) (21 ) — (221 ) Financing activities: Proceeds from sale of senior notes 996 — — — 996 Redemption of CODES (935 ) — — — (935 ) Common stock repurchased (823 ) — — — (823 ) Dividends paid on L3's common stock (208 ) — — — (208 ) Other financing activities 721 (530 ) (164 ) 50 77 Net cash used in financing activities from continuing operations (249 ) (530 ) (164 ) 50 (893 ) Effect of foreign currency exchange rate changes on cash — — (17 ) — (17 ) Net increase in cash and cash equivalents of discontinued operations — 46 — — 46 Change in cash balance in assets held for sale — (1 ) (60 ) — (61 ) Net increase (decrease) in cash 103 1 (119 ) (43 ) (58 ) Cash and cash equivalents, beginning of the year 258 — 261 (19 ) 500 Cash and cash equivalents, end of the year $ 361 $ 1 $ 142 $ (62 ) $ 442

Description of Business (Detail

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

Summary of Significant Accoun58

Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounting Estimates [Abstract]
Increase in operating income due to changes in contract estimates		$ 148	$ 52	$ 72
Percentage of increase in consolidated operating income due to changes in contract estimates		15.00%	11.00%	7.00%
Increase in operating income due to changes in contract estimates, diluted (in dollars per share)		$ 1.22	$ 0.45	$ 0.52
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
Accrued product warranty costs [Roll Forward]:
Balance at January 1	[1]	$ 105	$ 93
Acquisitions during this period	[1]	3	1
Accruals for product warranties issued during the period	[1]	51	59
Changes to accruals for product warranties existing before January 1	[1]	0	2
Foreign currency translation adjustments	[1]	(1)	(2)
Settlements made during the period	[1]	(49)	(48)
Balance at December 31	[1]	109	105	$ 93
Goodwill and Indefinite-lived Intangible Assets [Abstract]
Goodwill impairment charges	[2]	$ 0	384	$ 0
Discontinued Operations [Member]
Goodwill and Indefinite-lived Intangible Assets [Abstract]
Goodwill impairment charges			571
Continuing Operations [Member]
Goodwill and Indefinite-lived Intangible Assets [Abstract]
Goodwill impairment charges			384
NSS and Logistics Solutions [Member]
Goodwill and Indefinite-lived Intangible Assets [Abstract]
Goodwill impairment charges			955
NSS and Logistics Solutions [Member] | Discontinued Operations [Member]
Goodwill and Indefinite-lived Intangible Assets [Abstract]
Goodwill impairment charges			571
NSS and Logistics Solutions [Member] | Continuing Operations [Member]
Goodwill and Indefinite-lived Intangible Assets [Abstract]
Goodwill impairment charges			384
Minimum [Member] | Buildings and Improvements [Member]
Property, Plant and Equipment [Abstract]
Estimated useful life		10 years
Minimum [Member] | Machinery, Equipment, Furniture and Fixtures [Member]
Property, Plant and Equipment [Abstract]
Estimated useful life		3 years
Maximum [Member] | Buildings and Improvements [Member]
Property, Plant and Equipment [Abstract]
Estimated useful life		40 years
Maximum [Member] | Machinery, Equipment, Furniture and Fixtures [Member]
Property, Plant and Equipment [Abstract]
Estimated useful life		10 years
Electronic Systems [Member]
Goodwill and Indefinite-lived Intangible Assets [Abstract]
Goodwill impairment charges			$ 26
[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.
[2]	Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information.

Summary of Significant Accoun59

Summary of Significant Accounting Policies, Accounting Standards Issued and Not Yet Implemented (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Summary of Significant Accounting Policies [Line Items]
Percentage of net sales generated from revenue that use the units-of-delivery method	20.00%
ASU 2016-15 [Member]
Summary of Significant Accounting Policies [Line Items]
Debt extinguishment costs and original issue discounts	$ 11	$ 1

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 ($)	Jan. 22, 2016USD ($)	Oct. 13, 2015USD ($)	May 27, 2015USD ($)	May 27, 2015GBP (£)	Jan. 21, 2015USD ($)	Mar. 04, 2014USD ($)	Dec. 31, 2016USD ($)	Sep. 23, 2016USD ($)	Jun. 24, 2016USD ($)	Mar. 25, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 25, 2015USD ($)	Jun. 26, 2015USD ($)	Mar. 27, 2015USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Nov. 22, 2016GBP (£)	May 27, 2015GBP (£)
Business Acquisition [Line Items]
Fair value of liability, contingent consideration											$ 29				$ 0				$ 29	$ 0
Goodwill recognized											6,560				6,281				6,560	6,281	$ 6,512
Net sales											$ 2,989	$ 2,505	$ 2,664	$ 2,353	$ 2,871	$ 2,564	$ 2,543	$ 2,488	10,511	10,466	10,986
Income before income taxes																			850	$ 322	$ 872
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		252																				205
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
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
Advanced Technical Materials, Inc. [Member]
Business Acquisition [Line Items]
Purchase price of acquisition					$ 27
Goodwill recognized					$ 20
L3 MacDonald Humfrey, Micreo Aerosim and ATM [Member]
Business Acquisition [Line Items]
Net sales																			37
Income before income taxes																			$ 7
ForceX, Inc. [Member]
Business Acquisition [Line Items]
Purchase price of acquisition						$ 61
Goodwill recognized						53
Goodwill deductible for income tax purposes						$ 52
CTC Aviation Group [Member]
Business Acquisition [Line Items]
Purchase price of acquisition							$ 236	£ 153
Goodwill recognized							$ 182																£ 118
MITEQ, Inc. Acquisition [Member]
Business Acquisition [Line Items]
Purchase price of acquisition									$ 41
Goodwill recognized									11
Goodwill deductible for income tax purposes									$ 4
Data Tactics Corporation Acquisition [Member]
Business Acquisition [Line Items]
Purchase price of acquisition										$ 57
Goodwill recognized										$ 39
Implant Sciences Corporation [Member] | Subsequent Event [Member]
Business Acquisition [Line Items]
Purchase price of acquisition	$ 118

Acquisitions and Divestitures61

Acquisitions and Divestitures, Discontinued Operations (Details) - USD ($) $ in Millions		Feb. 01, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Discontinued Operations [Abstract]
Proceeds from sale of discontinued operations				$ 358
Net sales				209
Income (loss) from discontinued operations, net of income taxes			$ 63	(522)	$ 32
Gain (loss) on sale of business	[1]		0	(31)	0
Assets [Abstract]
Current assets			0	664	1,262
Liabilities [Abstract]
Current liabilities			0	220
NSS [Member]
Discontinued Operations [Abstract]
Net sales			86	1,088	1,138
Cost of sales			(92)	(1,040)	(1,065)
Gain related to business diverstiture	[2]		64	0	0
Goodwill impairment charges			0	(571)	0
Operating income (loss) from discontinued operations			58	(523)	73
Interest expense allocated to discontinued operations			0	(20)	(20)
Income (loss) from discontinued operations before income taxes			58	(543)	53
Income tax benefit (expense)			5	21	(21)
Income (loss) from discontinued operations, net of income taxes			63	(522)	$ 32
NSS [Member] | Discontinued Operations, Disposed of by Sale [Member]
Discontinued Operations [Abstract]
Gain (loss) on sale of business			$ 64
Assets [Abstract]
Current assets				201
Property, plant and equipment, net				25
Goodwill	[3]			390
Other assets				48
Total assets of discontinued operations				664
Liabilities [Abstract]
Accounts payable, trade				48
Other current liabilities				78
Current liabilities				126
Long-term liabilities				94
Total liabilities of discontinued operations				$ 220
CACI International Inc [Member] | Discontinued Operations, Disposed of by Sale [Member]
Discontinued Operations [Abstract]
Proceeds from sale of discontinued operations		$ 547
[1]	See Note 3 for information regarding the Company's business divestitures.
[2]	The year ended December 31, 2016 includes a gain of $64 million (before and after income taxes) on the sale of the NSS business.
[3]	The goodwill balance at December 31, 2015 is based on an allocation of the goodwill attributable to the NSS reporting unit to discontinued operations based on the relative fair value of the NSS business retained by L3 and NSS business sold.

Acquisitions and Divestitures62

Acquisitions and Divestitures, Business Divestitures (Details) € in Millions, $ in Millions		Jul. 27, 2015USD ($)	May 29, 2015USD ($)	Apr. 24, 2015USD ($)	Dec. 31, 2016USD ($)	Sep. 23, 2016USD ($)	Jun. 24, 2016USD ($)	Mar. 25, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 25, 2015USD ($)	Jun. 26, 2015USD ($)	Mar. 27, 2015USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	May 29, 2015EUR (€)
Business Divestiture [Abstract]
Loss related to business divestitures	[1]												$ 0	$ (31)	$ 0
Proceeds received														358
Net sales														209
Realized pre-tax loss on forward contract													(13)	(18)	(8)
Net sales					$ 2,989	$ 2,505	$ 2,664	$ 2,353	$ 2,871	$ 2,564	$ 2,543	$ 2,488	10,511	10,466	10,986
Income before income taxes													$ 850	322	872
Discontinued Operations [Member]
Business Divestiture [Abstract]
Net sales														209	596
Income before income taxes														0	$ 27
MSI [Member]
Business Divestiture [Abstract]
Loss related to business divestitures														(17)
Proceeds received														318
Net sales														185
Sale of business, sale price			$ 318													€ 295
Estimated employee pension related liabilities | €																€ 60
Gain (loss) on sale of business after income taxes														(6)
Pre-tax non-cash impairment charge														17
MSI [Member] | Foreign Currency Forward Contracts [Member]
Business Divestiture [Abstract]
Realized pre-tax loss on forward contract			$ (4)
BSI [Member]
Business Divestiture [Abstract]
Loss related to business divestitures				$ (4)										(4)
Proceeds received														26
Net sales														7
Sale of business, sale price				26
Gain (loss) on sale of business after income taxes				$ (6)
Tinsley Product Line [Member]
Business Divestiture [Abstract]
Loss related to business divestitures		$ (8)												(8)
Proceeds received														4
Net sales														9
Sale of business, sale price		4
Gain (loss) on sale of business after income taxes		$ (6)
Klein [Member]
Business Divestiture [Abstract]
Loss related to business divestitures														(2)
Proceeds received														10
Net sales														8
Sale of business, sale price									$ 10					10
Gain (loss) on sale of business after income taxes														$ (2)
[1]	See Note 3 for information regarding the Company's business divestitures.

Acquisitions and Divestitures63

Acquisitions and Divestitures, Unaudited Pro Forma Statements of Operations Data (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Acquisitions and Divestitures [Abstract]
Pro forma net sales	$ 10,655	$ 10,700
Pro forma income from continuing operations attributable to L3	660	307
Pro forma net income (loss) attributable to L-3	$ 723	$ (215)
Pro forma diluted earnings per share from continuing operations (in dollars per share)	$ 8.38	$ 3.74
Pro forma diluted earnings (loss) per share (in dollars per share)	$ 9.18	$ (2.63)

Contracts in Process (Details)

Contracts in Process (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Contracts Receivable [Abstract]
Unbilled contract receivables, gross	$ 2,020	$ 2,120
Unliquidated progress payments	(827)	(892)
Unbilled contract receivables, net	1,193	1,228
Inventoried contract costs, gross	1,065	975
Unliquidated progress payments	(203)	(122)
Inventoried contract costs, net	862	853
Total contracts in process	$ 2,055	2,081
Percentage of unbilled contract receivables, net billed and collected within one year	95.00%
Contracts Receivable [Line Items]
Percentage of incurred costs billed	80.00%
Summary of Inventory for Long Term Contracts or Programs [Roll Forward]
Amounts included in inventoried contract costs at beginning of the year	$ 137	114	$ 121
Contract costs incurred [Abstract]:
IRAD and B&P	308	284	270
Other G&A	839	822	804
Total	1,147	1,106	1,074
Amounts charged to cost of sales	(1,111)	(1,083)	(1,081)
Amounts included in inventoried contract costs at end of the year	173	137	114
Operating Expenses [Abstract]
Selling, general and administrative expenses	223	261	297
Research and development expenses	54	52	63
Total	$ 277	$ 313	$ 360
Maximum [Member]
Contracts Receivable [Line Items]
Number of years for billed and collected, unbilled contract receivables	1 year

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Inventories [Abstract]
Raw materials, components and sub-assemblies	$ 165	$ 164
Work in process	106	103
Finished goods	59	66
Total	$ 330	$ 333

Goodwill and Identifiable Int66

Goodwill and Identifiable Intangible Assets, Allocated by Reportable Segment (Details) $ in Millions		12 Months Ended
		Dec. 31, 2016USD ($)Employee	Dec. 31, 2015USD ($)		Dec. 31, 2014USD ($)
Goodwill [Line Items]
Approximate number of employees | Employee		38,000
Goodwill [Roll Forward]
Goodwill		$ 7,002	$ 6,723		$ 6,570
Accumulated impairment losses		(442)	(442)	[1]	(58)
Balance, Beginning		6,281	6,512
Business acquisitions	[2]	335	244
Business divestitures	[3]		(20)
Business retained from NSS divestiture			28
Goodwill impairment charges	[4]	0	(384)		0
Foreign currency translation adjustments	[5]	(56)	(99)
Balance, Ending		6,560	6,281		6,512
Vertex Aerospace [Member]
Goodwill [Roll Forward]
Goodwill impairment charges			(338)
Continuing Operations [Member]
Goodwill [Roll Forward]
Goodwill impairment charges			(384)
Continuing Operations [Member] | Vertex Aerospace [Member]
Goodwill [Roll Forward]
Goodwill impairment charges			(338)
Discontinued Operations [Member]
Goodwill [Roll Forward]
Goodwill impairment charges			(571)
Discontinued Operations [Member] | Vertex Aerospace [Member]
Goodwill [Roll Forward]
Goodwill impairment charges			0
NSS [Member]
Goodwill [Roll Forward]
Goodwill impairment charges			(608)
NSS [Member] | Continuing Operations [Member]
Goodwill [Roll Forward]
Goodwill impairment charges			(37)
NSS [Member] | Discontinued Operations [Member]
Goodwill [Roll Forward]
Goodwill impairment charges			(571)
Electronic Systems [Member]
Goodwill [Roll Forward]
Goodwill		4,246	3,994		3,816
Accumulated impairment losses		(69)	(69)	[1]	(43)
Balance, Beginning		3,925	3,773
Business acquisitions	[2]	315	233
Business divestitures	[3]		(20)
Business retained from NSS divestiture			26
Goodwill impairment charges			(26)
Foreign currency translation adjustments	[5]	(63)	(61)
Balance, Ending		4,177	3,925		3,773
Aerospace Systems [Member]
Goodwill [Roll Forward]
Goodwill		1,698	1,691		1,730
Accumulated impairment losses		(338)	(338)	[1]	0
Balance, Beginning		1,353	1,730
Business acquisitions	[2]	0	0
Business divestitures	[3]		0
Business retained from NSS divestiture			0
Goodwill impairment charges			(338)
Foreign currency translation adjustments	[5]	7	(39)
Balance, Ending		1,360	1,353		1,730
Communication Systems [Member]
Goodwill [Roll Forward]
Goodwill		1,058	1,038		1,024
Accumulated impairment losses		(35)	(35)	[1]	(15)
Balance, Beginning		1,003	1,009
Business acquisitions	[2]	20	11
Business divestitures	[3]		0
Business retained from NSS divestiture			2
Goodwill impairment charges			(20)
Foreign currency translation adjustments	[5]	0	1
Balance, Ending		$ 1,023	$ 1,003		$ 1,009
[1]	The accumulated impairment losses at December 31, 2015 exclude $571 million of impairment charges recorded during 2015 relating to the NSS reporting unit, which is reported in discontinued operations.
[2]	For the year ended December 31, 2016, the net increase in goodwill for the Electronic Systems segment was due to the L3 MacDonald Humfrey, Aeroism and Micreo business acquisitions, as well as the final purchase price allocations for the L3 ForceX and L3 CTC business acquisitions. The increase in goodwill for the Communication Systems segment was due to the ATM business acquisition. For the year ended December 31, 2015, the net increase in goodwill for the Electronic Systems segment was due to the L3 CTC and L3 ForceX business acquisitions. The increase in goodwill for the Communication Systems segment was due to the Miteq business acquisition.
[3]	For the year ended December 31, 2015, the decrease in goodwill for the Electronic Systems segment was due to the divestitures of BSI, the Tinsley Product Line and Klein.
[4]	Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information.
[5]	During 2016, the decrease in goodwill presented in the Electronic Systems segment was due to the strengthening of the U.S. dollar against the British pound, the Euro and the Australian dollar, offset by the weakening of the U.S. dollar against the Canadian dollar. The increase in goodwill presented in the Aerospace Systems segment was due to the weakening of the U.S. dollar against the Canadian dollar. During 2015, the decrease in goodwil presented in the Electronic Systems segment was primarily due to the strengthening of the U.S. dollar against the Canadian dollar, the British pound and the Euro. The decrease in goodwill presented in the Aerospace Systems segment was due to the strengthening of the U.S. dollar against the Canadian dollar.

Goodwill and Identifiable Int67

Goodwill and Identifiable Intangible Assets, Schedule of Adjustments Related to Goodwill Impairment Charges (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill impairment charges	[1]	$ 0	$ 384	$ 0
NSS [Member]
Goodwill [Line Items]
Goodwill impairment charges			608
Re-Allocation of Goodwill for Business Retained National Security Solutions [Member]
Goodwill [Line Items]
Goodwill impairment charges			9
NSS Business and Vertex Aerospace [Member]
Goodwill [Line Items]
Goodwill impairment charges			955
Vertex Aerospace [Member]
Goodwill [Line Items]
Goodwill impairment charges			338
Continuing Operations [Member]
Goodwill [Line Items]
Goodwill impairment charges			384
Continuing Operations [Member] | NSS [Member]
Goodwill [Line Items]
Goodwill impairment charges			37
Continuing Operations [Member] | Re-Allocation of Goodwill for Business Retained National Security Solutions [Member]
Goodwill [Line Items]
Goodwill impairment charges			9
Continuing Operations [Member] | Vertex Aerospace [Member]
Goodwill [Line Items]
Goodwill impairment charges			338
Discontinued Operations [Member]
Goodwill [Line Items]
Goodwill impairment charges			571
Discontinued Operations [Member] | NSS [Member]
Goodwill [Line Items]
Goodwill impairment charges			571
Discontinued Operations [Member] | Re-Allocation of Goodwill for Business Retained National Security Solutions [Member]
Goodwill [Line Items]
Goodwill impairment charges			0
Discontinued Operations [Member] | Vertex Aerospace [Member]
Goodwill [Line Items]
Goodwill impairment charges			$ 0
[1]	Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information.

Goodwill and Identifiable Int68

Goodwill and Identifiable Intangible Assets, Identifiable Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets Subject to Amortization [Abstract]
Weighted average amortization period	14 years
Gross carrying amount	$ 621	$ 547
Accumulated amortization	383	348
Net carrying amount	238	199
Amortization expense	35	35	$ 39
Estimated Amortization Expense for Identifiable Intangible Assets
Estimated amortization expense, 2017	39
Estimated amortization expense, 2018	35
Estimated amortization expense, 2019	32
Estimated amortization expense, 2020	28
Estimated amortization expense, 2021	$ 24
Customer Contractual Relationships [Member]
Finite-Lived Intangible Assets Subject to Amortization [Abstract]
Weighted average amortization period	15 years
Gross carrying amount	$ 409	370
Accumulated amortization	269	246
Net carrying amount	$ 140	124
Technology [Member]
Finite-Lived Intangible Assets Subject to Amortization [Abstract]
Weighted average amortization period	11 years
Gross carrying amount	$ 191	156
Accumulated amortization	102	91
Net carrying amount	$ 89	65
Other [Member]
Finite-Lived Intangible Assets Subject to Amortization [Abstract]
Weighted average amortization period	18 years
Gross carrying amount	$ 21	21
Accumulated amortization	12	11
Net carrying amount	$ 9	$ 10

Other Current Liabilities and69

Other Current Liabilities and Other Liabilities (Details) $ in Millions		Feb. 03, 2017USD ($)$ / shares	Dec. 31, 2015USD ($)	Dec. 31, 2016USD ($)
Other Current Liabilities [Abstract]
Estimated costs in excess of estimated contract value to complete contracts in process in a loss position			$ 75	$ 70
Accrued product warranty costs			70	68
Accruals for pending and threatened litigation (see Note 18)	[1]		6	51
Accrued interest			45	43
Deferred revenues			32	34
Product returns allowance	[1],[2]		20	5
Other			146	160
Total other current liabilities			394	431
Other Liabilities [Abstract]
Non-current income taxes payable (see Note 16)			161	124
Deferred compensation			45	47
Accrued product warranty costs			35	41
Accrued workers' compensation			38	30
Estimated contingent purchase price payable for acquired businesses (see Note 3)			0	29
Notes payable and capital lease obligations			10	13
Other			79	84
Total other liabilities			368	368
Accrued Liabilities And Deferred Credits [Line Items]
Accruals for pending and threatened litigation	[1]		6	51
Electronic Systems [Member] | EoTech HWS [Member]
Other Current Liabilities [Abstract]
Accruals for pending and threatened litigation (see Note 18)				14
Accrued Liabilities And Deferred Credits [Line Items]
Reduction to net sales			$ 20	18
Total expected cost of the voluntary return program				38
Accruals for pending and threatened litigation				$ 14
Electronic Systems [Member] | EoTech HWS [Member] | Subsequent Event [Member]
Accrued Liabilities And Deferred Credits [Line Items]
Approved refunds cost		$ 35
Average refund cost per unit (in dollars per unit) | $ / shares		500
[1]	The year ended December 31, 2016, includes $14 million accrued in the third quarter of 2016 in connection with the EoTech matter.
[2]	In November 2015, the Company commenced a voluntary return program and began accepting customer returns for various EoTech HWS products that may have been affected by certain performance issues. The return program gives eligible owners of such HWS products the option to return their products in exchange for a refund of the purchase price, including shipping costs. The Company initially recorded a reduction to net sales of $20 million in the Warrior Systems sector of the Electronic Systems segment in the fourth quarter of 2015 associated with establishing a product returns allowance to reflect the estimated cost of the return program. Beginning in the first quarter of 2016, with the benefit of a larger volume of actual refund transactions, the Company began using a statistical analysis of the voluntary return program to estimate the number and cost of future refunds. In its statistical analysis, the Company utilized empirical models to forecast the expected emergence pattern of new refunds over time to produce a probabilistic distribution of new refund costs that reflects the existing level of estimation uncertainty. Based on this analysis, the Company expects the total cost of the voluntary return program to be approximately $38 million. Accordingly, during 2016 the product returns allowance was increased by $18 million as a reduction to net sales. The product returns allowance, net of refund payments made to eligible owners, was $5 million at December 31, 2016. As of February 3, 2017, the Company had approved refunds at a cost of approximately $35 million, with an average refund cost per unit of $500. The Company will continue to monitor the product returns allowance. The Company's ongoing evaluation may cause it to record further adjustments to the allowance in future periods. These adjustments could be material.

Property, Plant and Equipment70

Property, Plant and Equipment (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Land	$ 54	$ 60
Buildings and improvements	438	431
Machinery, equipment, furniture and fixtures	1,890	1,736
Leasehold improvements	344	343
Gross property, plant and equipment	2,726	2,570
Accumulated depreciation and amortization	(1,605)	(1,473)
Property, plant and equipment, net	$ 1,121	$ 1,097

Debt, Components of Debt and Re

Debt, Components of Debt and Reconciliation to Carrying Amount of Current and Long-Term Debt (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Oct. 31, 2016
Components of Debt [Abstract]
Current portion of long-term debt		$ 0	$ (499)
Carrying amount of long-term debt, excluding current portion		3,325	3,127
Repayments under the credit facility		819	1,194	$ 1,367
Proceeds under the credit facility		819	1,194	$ 1,367
Available borrowings under credit facility		1,000	1,000
3.95% Senior Notes due 2016 [Member]
Components of Debt [Abstract]
Principal amount of long-term debt		200
5.20% Senior Notes due 2019 [Member]
Components of Debt [Abstract]
Unamortized discounts	[1]	(4)
4.75% Senior Notes due 2020 [Member]
Components of Debt [Abstract]
Unamortized discounts	[1]	(3)
4.95% Senior Notes due 2021 [Member]
Components of Debt [Abstract]
Unamortized discounts	[1]	(4)
3.95% Senior Notes due 2024 [Member]
Components of Debt [Abstract]
Unamortized discounts	[1]	(3)
3.85% Senior Notes due 2026 [Member]
Components of Debt [Abstract]
Unamortized discounts	[1]	$ (3)
Revolving Credit Facility [Member]
Amended and Restated Revolving Credit Facility [Abstract]
Revolving credit facility expiration period		5 years
Total aggregate borrowings under revolving credit facility					$ 1,000
Revolving credit facility expiration date		Oct. 31, 2021
Uncommitted incremental revolving facilities and additional term loan facilities					$ 600
Revolving Credit Facility [Member] | Federal Funds Rate [Member] | Minimum [Member]
Amended and Restated Revolving Credit Facility [Abstract]
Applicable spread on base rate		0.125%
Revolving Credit Facility [Member] | Federal Funds Rate [Member] | Maximum [Member]
Amended and Restated Revolving Credit Facility [Abstract]
Applicable spread on base rate		1.00%
Revolving Credit Facility [Member] | Eurodollar Rate [Member] | Minimum [Member]
Amended and Restated Revolving Credit Facility [Abstract]
Applicable spread on base rate		1.125%
Revolving Credit Facility [Member] | Eurodollar Rate [Member] | Maximum [Member]
Amended and Restated Revolving Credit Facility [Abstract]
Applicable spread on base rate		2.00%
L3 Technologies [Member]
Components of Debt [Abstract]
Borrowings under Revolving Credit Facility	[2]	$ 0	0
Principal amount of long-term debt		3,350	3,650
Unamortized discounts		(8)	(8)
Deferred debt issue costs		(17)	(16)
Carrying amount of long-term debt		3,325	3,626
Current portion of long-term debt		0	(499)
Carrying amount of long-term debt, excluding current portion		3,325	3,127
L3 Technologies [Member] | 3.95% Senior Notes due 2016 [Member]
Components of Debt [Abstract]
Borrowings under Revolving Credit Facility		$ 0	500
Interest rate on senior notes		3.95%
Debt instrument maturity period		2,016
L3 Technologies [Member] | 1.50% Senior Notes due 2017 [Member]
Components of Debt [Abstract]
Borrowings under Revolving Credit Facility		$ 0	350
Interest rate on senior notes		1.50%
Debt instrument maturity period		2,017
L3 Technologies [Member] | 5.20% Senior Notes due 2019 [Member]
Components of Debt [Abstract]
Borrowings under Revolving Credit Facility		$ 1,000	1,000
Interest rate on senior notes		5.20%
Debt instrument maturity period		2,019
L3 Technologies [Member] | 4.75% Senior Notes due 2020 [Member]
Components of Debt [Abstract]
Borrowings under Revolving Credit Facility		$ 800	800
Interest rate on senior notes		4.75%
Debt instrument maturity period		2,020
L3 Technologies [Member] | 4.95% Senior Notes due 2021 [Member]
Components of Debt [Abstract]
Borrowings under Revolving Credit Facility		$ 650	650
Interest rate on senior notes		4.95%
Debt instrument maturity period		2,021
L3 Technologies [Member] | 3.95% Senior Notes due 2024 [Member]
Components of Debt [Abstract]
Borrowings under Revolving Credit Facility		$ 350	350
Interest rate on senior notes		3.95%
Debt instrument maturity period		2,024
L3 Technologies [Member] | 3.85% Senior Notes due 2026 [Member]
Components of Debt [Abstract]
Borrowings under Revolving Credit Facility		$ 550	0
Interest rate on senior notes		3.85%
Debt instrument maturity period		2,026
L3 Technologies [Member] | Revolving Credit Facility [Member]
Components of Debt [Abstract]
Repayments under the credit facility		$ 819
Proceeds under the credit facility		819
Available borrowings under credit facility		$ 1,000	$ 1,000
[1]	Bond discounts are recorded as a reduction to the principal amount of the notes and are amortized as interest expense over the term of the notes.
[2]	During 2016, L3's aggregate borrowings and repayments under the Credit Facility were $819 million. L3 had the full availability of its $1 billion Credit Facility at December 31, 2016 and December 31, 2015.

Debt, Outstanding Senior Subord

Debt, Outstanding Senior Subordinated Notes (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Feb. 02, 2017
Outstanding Senior Note Terms [Abstract]
Net Cash Proceeds		$ 547	$ 0	$ 996
Net cash proceeds from senior unsecured notes		$ 988
Senior Notes Redemption [Abstract]
Tender date		Dec. 22, 2015
Debt Retirement Charge		$ (7)	(1)	0
Cash payments of senior notes		856	297	0
Repayments under the credit facility		$ 819	1,194	1,367
Conversion of converted securities				161
CODES Due 2035 [Member]
Outstanding Senior Note Terms [Abstract]
Interest rate on senior notes		3.00%
Senior Notes Redemption [Abstract]
Redemption Date	[1]	Jun. 20, 2014
Redemption amount	[1]	$ 700
Debt Retirement Charge	[1]	0
Redemption cash payments	[1]	$ 935
Interest rate on senior notes		3.00%
Sale of 3% Convertible Contingent Debt Securities by L-3 Holdings		$ 700
Conversion of converted securities		935
Excess of conversion value over fair value of the debt component		$ 161
Interest expense recognized				2
CODES Due 2035 [Member] | Subsequent Event [Member]
Senior Notes Redemption [Abstract]
Debt repurchased					$ 11
3.95% Senior Notes due 2016 [Member]
Outstanding Senior Note Terms [Abstract]
Redemption price as percentage of principal amount		101.475%
Senior Notes due		Nov. 15, 2016
Senior Notes Redemption [Abstract]
Redemption Date	[2]	May 20, 2016
Maturity date		Nov. 15, 2016
Redemption amount	[2]	$ 300
Principal Amount		200
Debt Retirement Charge	[2]	5
Redemption cash payments	[2]	305
Cash payments of senior notes		$ 200
1.50% Senior Notes due 2017 [Member]
Outstanding Senior Note Terms [Abstract]
Redemption price as percentage of principal amount		100.323%
Senior Notes Redemption [Abstract]
Redemption Date	[3]	Dec. 30, 2016
Redemption amount	[3]	$ 350
Debt Retirement Charge	[3]	2
Redemption cash payments	[3]	$ 351
5.20% Senior Notes due 2019 [Member]
Outstanding Senior Note Terms [Abstract]
Date of Issuance		Oct. 2, 2009
Amount Issued		$ 1,000
Discount	[4]	4
Net Cash Proceeds		$ 987
Effective Interest Rate		5.25%
Redemption at Treasury Rate	[5],[6]	30.00%
4.75% Senior Notes due 2020 [Member]
Outstanding Senior Note Terms [Abstract]
Date of Issuance		May 21, 2010
Amount Issued		$ 800
Discount	[4]	3
Net Cash Proceeds		$ 790
Effective Interest Rate		4.79%
Redemption at Treasury Rate	[5],[6]	25.00%
4.95% Senior Notes due 2021 [Member]
Outstanding Senior Note Terms [Abstract]
Date of Issuance		Feb. 7, 2011
Amount Issued		$ 650
Discount	[4]	4
Net Cash Proceeds		$ 639
Effective Interest Rate		5.02%
Redemption at Treasury Rate	[5],[6]	25.00%
3.95% Senior Notes due 2024 [Member]
Outstanding Senior Note Terms [Abstract]
Date of Issuance		May 28, 2014
Amount Issued		$ 650
Discount	[4]	3
Net Cash Proceeds	[7]	$ 641
Effective Interest Rate		4.02%
Redemption at Treasury Rate	[5],[6]	20.00%
Senior Notes Redemption [Abstract]
Tender amount		$ 300
Debt Retirement Charge		1
Tender cash payments		$ 297
3.85% Senior Notes due 2026 [Member]
Outstanding Senior Note Terms [Abstract]
Date of Issuance		Dec. 5, 2016
Amount Issued		$ 550
Discount	[4]	3
Net Cash Proceeds		$ 542
Effective Interest Rate		3.91%
Redemption at Treasury Rate	[5],[6]	25.00%
L3 Technologies [Member]
Outstanding Senior Note Terms [Abstract]
Discount		$ 8	8
Net Cash Proceeds		$ 547		$ 996
Redemption price as percentage of principal amount		101.00%
Senior Notes Redemption [Abstract]
Principal Amount		$ 3,350	3,650
Debt Retirement Charge		(7)	(1)
Cash payments of senior notes		$ 856	$ 297
L3 Technologies [Member] | Minimum [Member]
Outstanding Senior Note Terms [Abstract]
Redemption price as percentage of principal amount		100.00%
L3 Technologies [Member] | 3.95% Senior Notes due 2016 [Member]
Outstanding Senior Note Terms [Abstract]
Interest rate on senior notes		3.95%
Senior Notes Redemption [Abstract]
Interest rate on senior notes		3.95%
L3 Technologies [Member] | 1.50% Senior Notes due 2017 [Member]
Outstanding Senior Note Terms [Abstract]
Interest rate on senior notes		1.50%
Senior Notes Redemption [Abstract]
Interest rate on senior notes		1.50%
L3 Technologies [Member] | 5.20% Senior Notes due 2019 [Member]
Outstanding Senior Note Terms [Abstract]
Interest rate on senior notes		5.20%
Senior Notes Redemption [Abstract]
Interest rate on senior notes		5.20%
L3 Technologies [Member] | 4.75% Senior Notes due 2020 [Member]
Outstanding Senior Note Terms [Abstract]
Interest rate on senior notes		4.75%
Senior Notes Redemption [Abstract]
Interest rate on senior notes		4.75%
L3 Technologies [Member] | 4.95% Senior Notes due 2021 [Member]
Outstanding Senior Note Terms [Abstract]
Interest rate on senior notes		4.95%
Senior Notes Redemption [Abstract]
Interest rate on senior notes		4.95%
L3 Technologies [Member] | 3.95% Senior Notes due 2024 [Member]
Outstanding Senior Note Terms [Abstract]
Interest rate on senior notes		3.95%
Senior Notes Redemption [Abstract]
Interest rate on senior notes		3.95%
L3 Technologies [Member] | 3.95% Senior Notes due 2024 [Member] | Minimum [Member]
Outstanding Senior Note Terms [Abstract]
Senior Notes due		Feb. 28, 2024
Senior Notes Redemption [Abstract]
Maturity date		Feb. 28, 2024
L3 Technologies [Member] | 3.85% Senior Notes due 2026 [Member]
Outstanding Senior Note Terms [Abstract]
Interest rate on senior notes		3.85%
Senior Notes Redemption [Abstract]
Interest rate on senior notes		3.85%
L3 Technologies [Member] | 3.85% Senior Notes due 2026 [Member] | Minimum [Member]
Outstanding Senior Note Terms [Abstract]
Senior Notes due		Sep. 15, 2026
Senior Notes Redemption [Abstract]
Maturity date		Sep. 15, 2026
[1]	In 2005, L3 sold $700 million of 3% Convertible Contingent Debt Securities (CODES) due August 1, 2035. On February 2, 2011, L3 repurchased approximately $11 million of the CODES. The conversion value of CODES of $935 million was calculated in accordance with the indenture governing the CODES. L3 settled the entire conversion value with respect to converted CODES in cash. As a result of the conversion, the Company recorded a reduction to shareholders' equity of $161 million, related to the excess conversion value over the fair value of the debt component of the CODES, net of deferred tax liability. Interest expense recognized for the CODES was $2 million for the year ended December 31, 2014.
[2]	The redemption price was determined on May 17, 2016 at 101.475% of the principal amount. Interest ceased to accrue on and after May 20, 2016 and the only remaining right of holders of such Notes was to receive payment of the Redemption Price and accrued interest.
[3]	The Notes were redeemed at a price equal to 100.323%, plus accrued and unpaid interest, if any, to the redemption date. Interest ceased to accrue on and after the redemption date.
[4]	Bond discounts are recorded as a reduction to the principal amount of the notes and are amortized as interest expense over the term of the notes.
[5]	The Senior Notes maturing in 2019, 2020 and 2021 may be redeemed at any time prior to their maturity and the Senior Notes maturing in 2024 and 2026 may be redeemed at any time prior to February 28, 2024 and September 15, 2026, respectively, (three months prior to their maturity) at the option of L3, in whole or in part, at a redemption price equal to the greater of: (1) 100% of the principal amount, or (2) the present value of the remaining principal and interest payments discounted to the date of redemption, on a semi-annual basis, at the Treasury Rate (as defined in the indentures governing the Senior Notes), plus the spread indicated in the table above. In addition, if the Senior Notes maturing in 2024 and 2026 are redeemed at any time on or after February 28, 2024 and September 15, 2026, respectively, the redemption price would be equal to 100% of the principal amount.
[6]	Upon the occurrence of a change in control (as defined in the indentures governing the Senior Notes), each holder of the notes will have the right to require L3 to repurchase all or any part of such holder's notes at an offer price in cash equal to 101% of the aggregate principal amount plus accrued and unpaid interest, if any, to the date of purchase.
[7]	The net cash proceeds of $988 million (after deduction of the bond discount, underwriting expenses and commissions and other related expenses) were used primarily to fund the CODES retirement as discussed below. The remaining net proceeds were used for general corporate purposes.

Debt, Guarantees and Covenants

Debt, Guarantees and Covenants (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
L3 Technologies [Member]
Debt Instrument [Line Items]
Ownership percentage	100.00%
Minimum consolidated interest coverage ratio under revolving credit facility covenants	300.00%
Minimum consolidated senior leverage ratio under revolving credit facility covenants	375.00%
Maximum consolidated senior leverage ratio under revolving credit facility covenants	400.00%
Minimum aggregate amount of indebtedness, swap contracts or guarantees to trigger cross default provisions	$ 75
Maximum days to cure defaults triggering cross default provisions	10 days
Minimum aggregate amount of senior notes accelerated to trigger cross default provisions	$ 100
3.95% Senior Notes due 2024 [Member] | L3 Technologies [Member]
Debt Instrument [Line Items]
Interest rate on senior notes	3.95%
3.95% Senior Notes due 2024 [Member] | Minimum [Member] | L3 Technologies [Member]
Debt Instrument [Line Items]
Redemption date	Feb. 28, 2024
CODES Due 2035 [Member]
Debt Instrument [Line Items]
Interest rate on senior notes	3.00%

Accumulated Other Comprehensi74

Accumulated Other Comprehensive (Loss) Income (AOCI), Summary of AOCI Balances Including Amounts Reclassified from AOCI into Net Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	$ 4,355
Ending Balance	4,553	$ 4,355
Foreign Currency Translation Adjustments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(101)	19	$ 142
Other comprehensive (loss) income before reclassifications, net of tax	(77)	(161)	(123)
Amounts reclassified from AOCI, net of tax	0	41	0
Net current period other comprehensive (loss) income	(77)	(120)	(123)
Ending Balance	(178)	(101)	19
Unrealized Gains (Losses) on Hedging Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(8)	(5)	1
Other comprehensive (loss) income before reclassifications, net of tax	3	(15)	(13)
Amounts reclassified from AOCI, net of tax	11	12	7
Net current period other comprehensive (loss) income	14	(3)	(6)
Ending Balance	6	(8)	(5)
Unrecognized (Losses) Gains and Prior Service Cost, Net [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(465)	(598)	(253)
Other comprehensive (loss) income before reclassifications, net of tax	(119)	81	(354)
Amounts reclassified from AOCI, net of tax	30	52	9
Net current period other comprehensive (loss) income	(89)	133	(345)
Ending Balance	(554)	(465)	(598)
Accumulated Other Comprehensive Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(574)	(584)	(110)
Other comprehensive (loss) income before reclassifications, net of tax	(193)	(95)	(490)
Amounts reclassified from AOCI, net of tax	41	105	16
Net current period other comprehensive (loss) income	(152)	10	(474)
Ending Balance	$ (726)	$ (574)	$ (584)

Accumulated Other Comprehensi75

Accumulated Other Comprehensive (Loss) Income (AOCI), Summary of Amounts Reclassified from AOCI into Net Income (Details) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2016	Sep. 23, 2016	Jun. 24, 2016	Mar. 25, 2016	Dec. 31, 2015	Sep. 25, 2015	Jun. 26, 2015	Mar. 27, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of sales-products										$ (5,785)	$ (6,007)	$ (6,161)
Loss related to business divestitures	[1]									0	(31)	0
Income from continuing operations before income taxes										850	322	872
Provision for income taxes										(189)	(25)	(227)
Income from continuing operations		$ 192	$ 151	$ 151	$ 167	$ (56)	$ 128	$ 120	$ 105	661	297	645
MSI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Loss related to business divestitures											(17)
Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income from continuing operations	[2]									(41)	(105)	(16)
Foreign Currency Translation Adjustments [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income from continuing operations before income taxes	[2]									0	(41)	0
Income from continuing operations	[2]									0	(41)	0
Foreign Currency Translation Adjustments [Member] | Amount Reclassified from AOCI [Member] | MSI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Loss related to business divestitures	[2]									0	(41)	0
Losses on Hedging Instruments [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of sales-products	[2]									(13)	(16)	(8)
Income from continuing operations before income taxes	[2]									(13)	(18)	(8)
Provision for income taxes	[2]									2	6	1
Income from continuing operations	[2]									(11)	(12)	(7)
Losses on Hedging Instruments [Member] | Amount Reclassified from AOCI [Member] | MSI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Loss related to business divestitures	[2]									0	(2)	0
Amortization of Defined Benefit Pension Items [Member] | Amount Reclassified from AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net loss	[2],[3]									(48)	(67)	(15)
Income from continuing operations before income taxes	[2]									(48)	(81)	(15)
Provision for income taxes	[2]									18	29	6
Income from continuing operations	[2]									(30)	(52)	(9)
Amortization of Defined Benefit Pension Items [Member] | Amount Reclassified from AOCI [Member] | MSI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Loss related to business divestitures	[2]									$ 0	$ (14)	$ 0
[1]	See Note 3 for information regarding the Company's business divestitures.
[2]	Amounts in parentheses indicate charges to the consolidated statements of operations.
[3]	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, shares in Millions, $ in Millions	Feb. 13, 2017	Feb. 17, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 04, 2014
Class of Stock [Line Items]
Aggregate amount of repurchased shares			$ 373	$ 740	$ 823
Cash dividends declared per common share (in dollars per share)			$ 2.80	$ 2.60	$ 2.40
Dividend declared date			Feb. 13, 2017
Dividend paid date			Mar. 15, 2017
Dividend paid, record date			Mar. 1, 2017
Cash dividends			$ 220	$ 213	$ 209
Subsequent Event [Member]
Class of Stock [Line Items]
Cash dividends declared per common share (in dollars per share)	$ 0.75
Treasury Stock [Member]
Class of Stock [Line Items]
Aggregate amount of repurchased shares			$ 373	$ 740	$ 823
Share Repurchase Program December 4, 2014 [Member]
Class of Stock [Line Items]
Amount of shares authorized to be repurchased						$ 1,500
Average price per share of repurchased shares (in dollars per share)			$ 123.95
Aggregate amount of repurchased shares			$ 373
Remaining authorized amount of share repurchase programs			$ 433
Share Repurchase Program December 4, 2014 [Member] | Treasury Stock [Member]
Class of Stock [Line Items]
Number of common shares repurchased (in shares)			3
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)		0

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Millions		Dec. 31, 2016	Dec. 31, 2015
Liabilities [Abstract]
Contingent consideration		$ 29	$ 0
Recurring [Member] | Level 1 [Member]
Assets [Abstract]
Cash equivalents	[1]	104	187
Derivatives (foreign currency forward contracts)	[1]	0	0
Total assets	[1]	104	187
Liabilities [Abstract]
Derivatives (foreign currency forward contracts)	[1]	0	0
Contingent consideration	[1],[2]	0	0
Total liabilities	[1]	0	0
Recurring [Member] | Level 2 [Member]
Assets [Abstract]
Cash equivalents	[3]	0	0
Derivatives (foreign currency forward contracts)	[3]	12	2
Total assets	[3]	12	2
Liabilities [Abstract]
Derivatives (foreign currency forward contracts)	[3]	6	16
Contingent consideration	[2],[3]	0	0
Total liabilities	[3]	6	16
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]	29	0
Total liabilities	[4]	$ 29	$ 0
[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 L3 MacDonald Humfrey acquisition. The fair value of the contingent consideration liability is based on a Monte Carlo Simulation of the aggregate revenue of L3 MacDonald Humfrey 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 L3 MacDonald Humfrey 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		Dec. 31, 2016	Dec. 31, 2015
Carrying Amount [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes	[1]	$ 3,325	$ 3,626
Foreign currency forward contracts	[2]	6	(14)
Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes	[1]	3,526	3,754
Foreign currency forward contracts	[2]	$ 6	$ (14)
[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 14 for additional disclosures regarding the notional amounts and fair values of foreign currency forward contracts.

Derivative Financial Instrume79

Derivative Financial Instruments, Outstanding Forward Contracts By Currency (Details) - Foreign Currency Forward Contracts [Member] $ in Millions	Dec. 31, 2016USD ($)
Derivative [Line Items]
Notional amount of foreign currency forward contracts	$ 358
U.S. Dollar [Member]
Derivative [Line Items]
Notional amount of foreign currency forward contracts	117
Euro [Member]
Derivative [Line Items]
Notional amount of foreign currency forward contracts	109
Canadian Dollar [Member]
Derivative [Line Items]
Notional amount of foreign currency forward contracts	96
British Pound [Member]
Derivative [Line Items]
Notional amount of foreign currency forward contracts	28
Other [Member]
Derivative [Line Items]
Notional amount of foreign currency forward contracts	$ 8

Derivative Financial Instrume80

Derivative Financial Instruments, Fair Value on Consolidated Balance Sheet (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Realized pre-tax loss on forward contract		$ (13)	$ (18)	$ (8)
Estimated net amount of existing (losses) expected to be reclassified into income within the next 12 months		5
Other Current Assets [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, assets		10	1
Other Current Assets [Member] | Foreign Currency Forward Contracts [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, assets	[1]	10	1
Other Assets [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, assets		2	1
Other Assets [Member] | Foreign Currency Forward Contracts [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, assets	[1]	2	1
Other Current Liabilities [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, liabilities		6	15
Other Current Liabilities [Member] | Foreign Currency Forward Contracts [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, liabilities	[1]	6	15
Other Liabilities [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, liabilities		0	1
Other Liabilities [Member] | Foreign Currency Forward Contracts [Member] | Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Total derivative instruments, liabilities	[1]	$ 0	$ 1
[1]	See Note 12 for a description of the fair value hierarchy related to the Company's foreign currency forward contracts.

L3's Earnings Per Share, Reconc

L3's Earnings Per Share, Reconciliation of Basic and Diluted Earnings Per Share (EPS) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended																12 Months Ended
		Dec. 31, 2016		Sep. 23, 2016		Jun. 24, 2016		Mar. 25, 2016		Dec. 31, 2015		Sep. 25, 2015		Jun. 26, 2015		Mar. 27, 2015		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of net income (loss) [Abstract]
Net income (loss)		$ 192		$ 151		$ 151		$ 230		$ (162)		$ (296)		$ 124		$ 109		$ 724	$ (225)	$ 677
Net income from continuing operations attributable to noncontrolling interests																		(14)	(15)	(13)
Net income (loss) attributable to L3		$ 188		$ 148		$ 147		$ 227		$ (166)		$ (299)		$ 120		$ 105		710	(240)	664
Earnings (loss) attributable to L3's common shareholders: [Abstract]
Continuing operations																		647	282	632
Discontinued operations, net of income tax																		63	(522)	32
Net income (loss) attributable to L3 common shareholders																		$ 710	$ (240)	$ 664
Basic [Abstract]
Weighted average common shares outstanding (in shares)																		77.4	80.7	85.4
Basic earnings (loss) per share [Abstract]
Continuing operations (in dollars per share)		$ 2.43	[1]	$ 1.91	[1]	$ 1.90	[1]	$ 2.11	[1]	$ (0.76)	[1]	$ 1.56	[1]	$ 1.41	[1]	$ 1.23	[1]	$ 8.36	$ 3.49	$ 7.40
Discontinued operations, net of income tax (in dollars per share)																		0.81	(6.46)	0.38
Basic earnings (loss) per share (in dollars per share)		2.43	[1]	1.91	[1]	1.90	[1]	2.92	[1]	(2.11)	[1]	(3.74)	[1]	1.46	[1]	1.28	[1]	$ 9.17	$ (2.97)	$ 7.78
Common and potential common shares [Abstract]
Weighted average common shares outstanding (in shares)																		77.4	80.7	85.4
Assumed purchase of common shares for treasury (in shares)																		(2.4)	(2.7)	(3.1)
Assumed conversion of the CODES (in shares)	[2]																	0	0	0.8
Common and potential common shares (in shares)																		78.8	81.9	87.8
Diluted earnings (loss) per share [Abstract]
Continuing operations (in dollars per share)		2.38	[1]	1.88	[1]	1.88	[1]	2.08	[1]	(0.76)	[1]	1.54	[1]	1.39	[1]	1.20	[1]	$ 8.21	$ 3.44	$ 7.20
Discontinued operations, net of income tax (in dollars per share)																		0.80	(6.37)	0.36
Diluted earnings (loss) per share (in dollars per share)		$ 2.38	[1]	$ 1.88	[1]	$ 1.88	[1]	$ 2.87	[1]	$ (2.11)	[1]	$ (3.68)	[1]	$ 1.44	[1]	$ 1.25	[1]	$ 9.01	$ (2.93)	$ 7.56
Stock Options [Member]
Common and potential common shares [Abstract]
Common and potential common shares (in shares)																		2.6	2.4	3
Unvested Restricted Stock Awards [Member]
Common and potential common shares [Abstract]
Common and potential common shares (in shares)																		1	1.3	1.6
Performance Unit Awards [Member]
Common and potential common shares [Abstract]
Common and potential common shares (in shares)																		0.1	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	0
[1]	EPS in each quarter is computed using the weighted-average number of shares outstanding during that quarter, while EPS for the full year is computed using the weighted-average number of shares outstanding during the year. Therefore, the sum of the four quarters' EPS may not equal the full year computed EPS.
[2]	The CODES were retired on June 20, 2014 and were dilutive for the year ended December 31, 2014 as the average market price of L3's common stock during the period that the CODES were outstanding was greater than the price at which the CODES would have been convertible into L3's common stock. As of June 18, 2014, the final date of conversion, the conversion price was $88.71.

L3's Earnings Per Share (Detail

L3's Earnings Per Share (Details) - $ / shares shares in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jun. 18, 2014
Subsidiary, Sale of Stock [Line Items]
Shares excluded from computation of diluted earnings per share (in shares)	0.4	0.6	0.5
CODES Due 2035 [Member]
Subsidiary, Sale of Stock [Line Items]
Conversion price of L-3 Holdings' CODES (in dollars per share)				$ 88.71

Income Taxes, Income from Conti

Income Taxes, Income from Continuing Operations Before Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Abstract]
Domestic	$ 654	$ 192	$ 707
Foreign	196	130	165
Income from continuing operations before income taxes	$ 850	$ 322	$ 872

Income Taxes, Components of Cur

Income Taxes, Components of Current and Deferred Portions of Provision for Income Taxes on Continuing Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current income tax provision [Abstract]
Federal	$ 88	$ 60	$ 78
State and local	10	5	1
Foreign	48	26	35
Subtotal	146	91	114
Deferred income tax provision/(benefit) [Abstract]
Federal	37	(67)	101
State and local	6	(1)	11
Foreign	0	2	1
Subtotal	43	(66)	113
Total provision for income taxes	$ 189	$ 25	$ 227

Income Taxes, Reconciliation of

Income Taxes, Reconciliation of Statutory Federal Income Tax Rate to Effective Income Tax Rate on Continuing Operations (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014
Income Taxes [Abstract]
Statutory federal income tax rate		35.00%	35.00%		35.00%
State and local income taxes, net of federal income tax benefit		2.30%	2.00%		2.10%
Foreign income taxes		(2.90%)	(14.20%)		(3.60%)
Manufacturing benefits		(2.20%)	(3.70%)		(1.70%)
Research and experimentation and other tax credits		(4.40%)	(12.90%)		(4.30%)
Resolution of tax contingencies		(2.90%)	(2.80%)		(1.00%)
Tax deductible dividends		(0.90%)	(2.30%)		(0.80%)
Equity compensation - excess income tax benefits		(2.00%)	0.00%		0.00%
Goodwill Impairment		0.00%	6.60%		0.00%
Other, net		0.20%	0.10%		0.30%
Effective income tax rate on continuing operations		22.20%	7.80%	[1]	26.00%
Non-cash goodwill impairment charges	[2]	$ 0	$ 384		$ 0
Deferred tax benefit			$ (120)
Effective income tax rate excluding goodwill impairment charge and related income tax benefit			20.50%
[1]	In 2015, the Company recorded non-cash goodwill impairment charges of $384 million, which resulted in a deferred tax benefit of $120 million. Excluding the goodwill impairment charge and the related deferred income tax benefit, the effective income tax rate for 2015 would have been 20.5%.
[2]	Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information.

Income Taxes, Components of Net

Income Taxes, Components of Net Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Deferred tax assets [Abstract]
Inventoried costs	$ 63	$ 56
Compensation and benefits	152	147
Pension and postretirement benefits	415	354
Loss carryforwards	18	12
Tax credit carryforwards	6	6
Other	89	79
Deferred tax assets	743	654
Less: valuation allowance	(12)	(9)
Deferred tax assets, net of valuation allowance	731	645
Deferred tax liabilities [Abstract]
Goodwill and other intangible assets	(752)	(675)
Income recognition on contracts in process	(63)	(36)
Property, plant and equipment	(96)	(94)
Other	(54)	(56)
Deferred tax liabilities	(965)	(861)
Total deferred tax liabilities, net of valuation allowance	$ (234)	$ (216)

Income Taxes, Classification of

Income Taxes, Classification of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
Non-current deferred tax assets	$ 2	$ 3
Non-current deferred tax liabilities	(236)	(219)
Total deferred tax liabilities, net of valuation allowance	$ (234)	$ (216)

Income Taxes, Summary of Loss a

Income Taxes, Summary of Loss and Tax Credit Carryforwards (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Tax Effected	$ 18	$ 12
Capital loss carryforwards, Valuation Allowance, Tax Effected	12	9
Total loss carryforwards, Tax Effected	18
Tax credit carryforwards, Tax Effected	6	$ 6
Tax credit carryforwards, Valuation Allowances Tax Effected	4
Federal [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Gross	33
Capital loss carryforwards, Tax Effected	11
Capital loss carryforwards, Valuation Allowance, Gross	5
Capital loss carryforwards, Valuation Allowance, Tax Effected	$ 2
Federal [Member] | Minimum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2,026
Federal [Member] | Maximum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2,035
Foreign [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Gross	$ 14
Capital loss carryforwards, Tax Effected	3
Capital loss carryforwards, Valuation Allowance, Gross	3
Capital loss carryforwards, Valuation Allowance, Tax Effected	1
Tax credit carryforwards, Tax Effected	1
Tax credit carryforwards, Gross	1
Tax credit carryforwards, Valuation Allowances Gross	0
Tax credit carryforwards, Valuation Allowances Tax Effected	0
State [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Gross	136
Capital loss carryforwards, Tax Effected	2
Capital loss carryforwards, Valuation Allowance, Gross	47
Capital loss carryforwards, Valuation Allowance, Tax Effected	1
Tax credit carryforwards, Tax Effected	5
Tax credit carryforwards, Gross	7
Tax credit carryforwards, Valuation Allowances Gross	7
Tax credit carryforwards, Valuation Allowances Tax Effected	$ 4
State [Member] | Minimum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2,017
Tax credit carryforwards, Expiration Periods	2,017
State [Member] | Maximum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2,036
Tax credit carryforwards, Expiration Periods	2,031
Capital Loss Carryforwards [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Gross	$ 6
Capital loss carryforwards, Tax Effected	2
Capital loss carryforwards, Valuation Allowance, Gross	6
Capital loss carryforwards, Valuation Allowance, Tax Effected	$ 2
Capital Loss Carryforwards [Member] | Minimum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2,017
Capital Loss Carryforwards [Member] | Maximum [Member]
Tax Credit Carryforward [Line Items]
Capital loss carryforwards, Expiration Period	2,021

Income Taxes, Reconciliation 89

Income Taxes, Reconciliation of Change in Unrecognized Income Tax Benefits, Excluding Interest and Penalties (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016
Income Taxes [Abstract]
Unrecognized tax benefits	$ 111	$ 169	$ 169	$ 111
Unrecognized tax benefits that would reduce the effective income tax rate				$ 92
Reconciliation of Change in Unrecognized Income Tax Benefits, Excluding Interest and Penalties [Roll Forward]
Balance at January 1	140	169	155
Additions for tax positions related to the current year	16	14	20
Additions for tax positions related to prior years	2	2	12
Reductions for tax positions related to prior years	(39)	(37)	(11)
Reductions for tax positions related to settlements with taxing authorities	(1)	(1)	(1)
Reduction for tax positions related to prior years as a result of a lapse of statute of limitations	(7)	(7)	(6)
Balance at December 31	$ 111	$ 140	$ 169

Income Taxes, Income Tax Return

Income Taxes, Income Tax Returns (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Abstract]
Anticipated decrease in unrecognized tax benefits over the next 12 months	$ 9
Reversal of previously accrued income tax expense, including interest and penalties	25	$ 9	$ 8
Change in previously accrued income tax expenses related to tax returns			$ 8
Accrued potential interest included within current and non-current income taxes payable	11	18
Accrued potential interest included within current and non-current income taxes payable after income taxes	7	11
Potential penalties	8	9
Benefit (Expense) Related Items Included in Income Taxes Expenses	(4)	2
Deferred taxes for the repatriation of earnings from certain subsidiaries		$ 17
Undistributed earnings of non-U.S. Companies	$ 708

Stock-Based Compensation, Stock

Stock-Based Compensation, Stock-Based Compensation Plans (Details) - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2016		Dec. 31, 2015	Dec. 31, 2014	May 03, 2016	Feb. 23, 2016	Feb. 22, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of L-3 Holdings common stock available to be awarded (in shares)						4,260	3,690
Share-based Compensation Arrangement by Share-based Payment Award [Abstract]
Stock based compensation	$ 49		$ 49	$ 52
Income taxes	(18)		(18)	(20)
Total after income taxes	31		31	32
Less: Stock-based compensation recorded in discontinued operations, net of income taxes	1	[1]	1	1
Stock-based compensation recorded in continuing operations, net of income taxes	30		30	31
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Abstract]
Stock based compensation	10		9	9
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Abstract]
Stock based compensation	35		38	40
Performance Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Abstract]
Stock based compensation	$ 4		$ 2	$ 3
2008 Long Term Performance Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of additional shares authorized for issuance under the amendment (in shares)					6,800
Number of shares authorized for issuance under the amendment (in shares)					26,000
Maximum number of shares of L-3 Holdings common stock may be issued pursuant to "full value" awards under the amendment (in shares)	9,200
[1]	Amount relates to the net impact of share based payment award modification in connection with the sale of NSS, which is further discussed below.

Stock-Based Compensation, Sto92

Stock-Based Compensation, Stock Options (Details) - Stock Options [Member] - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
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)		$ 15.90	$ 19.76	$ 20.02
Intrinsic value of stock options exercised		$ 34	$ 35	$ 43
Unrecognized compensation costs related to equity awards after income taxes		6
Unrecognized compensation costs related to stock awards		$ 9
Weighted average remaining period for recognition of unrecognized costs related to equity awards		1 year 4 months 24 days
Actual income tax benefit realized related to compensation deductions arising from the exercise of stock options		$ 12	$ 13	$ 14
Number of Options [Roll Forward]
Beginning Balance, Outstanding (in shares)		2,931,500
Options granted (in shares)		617,600
Options exercised (in shares)		(647,500)
Options forfeited (in shares)		(54,100)
Ending Balance, Outstanding (in shares)		2,847,500	2,931,500
Vested and expected to vest (in shares)	[1]	2,835,700
Exercisable (in shares)		1,802,000
Weighted Average Exercise Price [Abstract]
Beginning Balance, Outstanding (in dollars per share)		$ 92.59
Options granted (in dollars per share)		116.68
Options exercised (in dollars per share)		82.78
Options forfeited (in dollars per share)		118.82
Ending Balance, Outstanding (in dollars per share)		99.54	$ 92.59
Vested and expected to vest (in dollars per share)	[1]	99.46
Exercisable (in dollars per share)		$ 87.77
Weighted Average Remaining Contractual Term [Abstract]
Weighted Average Remaining Contractual Term, Outstanding		6 years 1 month 6 days	6 years
Vested and expected to vest	[1]	6 years 1 month 6 days
Exercisable		4 years 10 months 24 days
Aggregate Intrinsic Value [Abstract]
Beginning Balance, Outstanding		$ 84
Ending Balance, Outstanding		150	$ 84
Vested and expected to Vest	[1]	149
Exercisable		$ 116
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected holding period		5 years	5 years	5 years 6 months
Expected volatility		21.30%	21.40%	24.40%
Expected dividend yield		2.80%	2.40%	2.70%
Risk-free interest rate		1.10%	1.50%	1.70%
[1]	Represents outstanding options reduced by expected forfeitures for options not fully vested.

Stock-Based Compensation, Restr

Stock-Based Compensation, Restricted Stock Units (Details) - Restricted Stock Units [Member] - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Weighted average grant date fair value (in dollars per share)	$ 116.72	$ 128.59	$ 113.58
Length of service after grant date	1 year
Age of retirement eligible employees	65 years
Unrecognized compensation costs related to stock awards	$ 38
Unrecognized compensation costs related to equity awards after income taxes	$ 24
Weighted average remaining period for recognition of unrecognized costs related to equity awards	1 year 2 months 12 days
Fair value of restricted stock unit awards vested	$ 57	$ 82	$ 66
Nonvested, Number of Shares [Roll Forward]
Beginning Balance, Nonvested (in shares)	1,171,900
Granted (in shares)	397,600
Vested (in shares)	(478,300)
Forfeited (in shares)	(113,300)
Ending Balance, Nonvested (in shares)	977,900	1,171,900
Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Beginning Balance, Nonvested (in dollars per share)	$ 102.91
Granted (in dollars per share)	116.72	$ 128.59	$ 113.58
Vested (in dollars per share)	76.83
Forfeited (in dollars per share)	111.89
Ending Balance, Nonvested (in dollars per share)	$ 120.24	$ 102.91
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Length of service for retirement eligible employees	5 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 Units [Member] - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)	$ 116.20	$ 129.03	$ 113.67
Length of service after grant date	3 years	3 years	3 years
Unrecognized compensation costs related to equity awards after income taxes	$ 4
Unrecognized compensation costs related to stock awards	$ 6
Weighted average remaining period for recognition of unrecognized costs related to equity awards	1 year 7 months 6 days
Total performance units earned	0
Nonvested, Number of Shares [Roll Forward]
Beginning Balance, Nonvested (in shares)	39,600
Granted (in shares)	51,900
Increase due to expected performance (in shares)	35,600
Vested (in shares)	0
Forfeited (in shares)	(2,400)
Ending Balance, Nonvested (in shares)	124,700	39,600
Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Beginning Balance, Nonvested (in dollars per share)	$ 121.27
Granted (in dollars per share)	116.20	$ 129.03	$ 113.67
Increase due to expected performance (in dollars per share)	127.14
Vested (in dollars per share)	0
Forfeited (in dollars per share)	121.72
Ending Balance, Nonvested (in dollars per share)	$ 120.83	$ 121.27
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout Range	200.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout Range	0.00%

Stock-Based Compensation, Emplo

Stock-Based Compensation, Employee Stock Purchase Plan (Details) $ / shares in Units, shares in Millions	Jan. 31, 2017$ / sharesshares	Feb. 01, 2016USD ($)Employee	Dec. 31, 2016USD ($)$ / sharesshares	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	May 03, 2016shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee discount on the purchase of common stock			5.00%
Stock compensation expense on cash payments made			$ 49,000,000	$ 49,000,000	$ 52,000,000
NSS [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees held unvested restricted stock unit and stock option awards | Employee		300
Vesting period		3 years
Reversed previously recorded stock compensation expense relating to the original awards		$ 4,000,000
Stock compensation expense on cash payments made		$ 5,000,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Stock compensation expense on cash payments made			$ 10,000,000	9,000,000	9,000,000
Unvested Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Stock compensation expense on cash payments made			$ 35,000,000	38,000,000	40,000,000
Unvested Restricted Stock Awards [Member] | Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			1 year
Performance Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense on cash payments made			$ 4,000,000	$ 2,000,000	$ 3,000,000
2008 Long Term Performance Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for issuance under the amendment (in shares) | shares						26
2009 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair market value for offering period			95.00%
Share purchases funded through payroll deductions, value			$ 21,250
Issued shares under the ESPP (in shares) | shares			0.1
Average price of issued shares under the ESPP (in dollars per share) | $ / shares			$ 137.87
Number of shares authorized for issuance under the amendment (in shares) | shares			3.7
2009 Employee Stock Purchase Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share purchases funded through payroll deductions, percentage			10.00%
2009 Employee Stock Purchase Plan [Member] | Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issued shares under the ESPP (in shares) | shares	0.1
Average price of issued shares under the ESPP (in dollars per share) | $ / shares	$ 144.73

Commitments and Contingencies,

Commitments and Contingencies, Non-Cancelable Operating Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Future Minimum Payments under Non-Cancelable Operating Leases [Abstract]
2,017	$ 99
2,018	84
2,019	65
2,020	90
2,021	45
Thereafter	213
Total minimum payments required	596
Less: Sublease rentals under non-cancelable leases	10
Net minimum payments required	586
Rent expense, net of sublease income	101	$ 104	$ 117
Sublease rental income	2	$ 2	$ 1
Real Estate [Member]
Future Minimum Payments under Non-Cancelable Operating Leases [Abstract]
2,017	94
2,018	81
2,019	63
2,020	90
2,021	45
Thereafter	213
Total minimum payments required	586
Less: Sublease rentals under non-cancelable leases	10
Net minimum payments required	576
Equipment [Member]
Future Minimum Payments under Non-Cancelable Operating Leases [Abstract]
2,017	5
2,018	3
2,019	2
2,020	0
2,021	0
Thereafter	0
Total minimum payments required	10
Less: Sublease rentals under non-cancelable leases	0
Net minimum payments required	$ 10

Commitments and Contingencies97

Commitments and Contingencies, Letters of Credit and Guarantees (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)Agreement	Dec. 31, 2015USD ($)
Loss Contingencies [Line Items]
Total outstanding letters of credit	$ 402	$ 425
Available borrowings under Credit Facility	$ 1,000	$ 1,000
Number of existing real estate lease agreements | Agreement	3
Real estate lease agreements, expiry date	Aug. 31, 2020
Purchase price of property on or before expiration date	$ 45
Residual guarantee amount	39
Maximum amount of supplemental rent payment	6
Aggregate residual guarantee amount	$ 39
Simulator Systems [Member]
Loss Contingencies [Line Items]
Operating lease agreements, term of contract	15 years
Operating lease, date of expiration	Mar. 31, 2018
Operating lease, additional rent	$ 7
Simulator Systems [Member] | Minimum [Member]
Loss Contingencies [Line Items]
Fair market value simulator systems	7
Simulator Systems [Member] | Maximum [Member]
Loss Contingencies [Line Items]
Fair market value simulator systems	$ 21

Commitments and Contingencies98

Commitments and Contingencies, Litigation Matters (Details) € in Millions, $ in Millions	Jan. 11, 2017USD ($)	Dec. 20, 2016USD ($)	Jul. 23, 2014EUR (€)	Aug. 31, 2016Complaint	Mar. 31, 2016Complaint	Feb. 29, 2016Complaint	Aug. 31, 2014Complaint	Sep. 23, 2016USD ($)	Dec. 31, 2016USD ($)
Contingencies And Commitments [Line Items]
Recoveries from insurance contracts in connection with liabilities amount									$ 34.5
Pre tax charge amount								$ 14
EoTech Class Actions [Member]
Contingencies And Commitments [Line Items]
Number of putative class action complaints against entity | Complaint					2	3
Number of putative class action complaints against entity consolidated | Complaint				5
Securities Class Action [Member]
Contingencies And Commitments [Line Items]
Number of putative class action complaints against entity and officers | Complaint							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
Subsequent Event [Member] | Civil Penalty [Member]
Contingencies And Commitments [Line Items]
Settlement paid	$ 1.6

Pensions and Other Employee B99

Pensions and Other Employee Benefits, Changes in Benefit Obligations, Plan Assets and Funded Status and Aggregate Balance Sheet Impact (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assets and (liabilities) recognized on the consolidated balance sheets consist of [Abstract]
Non-current liabilities	$ (1,177)	$ (1,047)
Pension Plans [Member]
Change in benefit obligation [Abstract]
Benefit obligation at the beginning of the year	3,448	3,663
Service cost	108	123	$ 106
Interest cost	135	149	147
Plan participants' contributions	2	2
Amendments	15
Actuarial loss (gain)	167	(261)
Foreign currency exchange rate changes	9	(53)
Curtailments, settlements and special termination benefits	2	3
Business divestiture	0	(59)
Benefits paid	(128)	(119)
Benefit obligation at the end of the year	3,758	3,448	3,663
Change in plan assets [Abstract]
Fair value of plan assets at the beginning of the year	2,552	2,570
Actual return on plan assets	189	54
Employer contributions	97	97
Plan participants' contributions	2	2
Foreign currency exchange rate changes	9	(52)
Benefits paid	(128)	(119)
Fair value of plan assets at the end of the year	2,721	2,552	2,570
Unfunded status at the end of the year	(1,037)	(896)
Assets and (liabilities) recognized on the consolidated balance sheets consist of [Abstract]
Non-current assets	37	37
Current liabilities	(6)	(5)
Non-current liabilities	(1,068)	(928)
Total	(1,037)	(896)
Postretirement Benefit Plans [Member]
Change in benefit obligation [Abstract]
Benefit obligation at the beginning of the year	184	199
Service cost	2	3	3
Interest cost	6	7	8
Plan participants' contributions	4	4
Amendments	(3)
Actuarial loss (gain)	(3)	(12)
Foreign currency exchange rate changes	0	(4)
Curtailments, settlements and special termination benefits	0	0
Business divestiture	0	0
Benefits paid	(13)	(13)
Benefit obligation at the end of the year	177	184	199
Change in plan assets [Abstract]
Fair value of plan assets at the beginning of the year	57	60
Actual return on plan assets	5	0
Employer contributions	7	6
Plan participants' contributions	4	4
Foreign currency exchange rate changes	0	0
Benefits paid	(13)	(13)
Fair value of plan assets at the end of the year	60	57	$ 60
Unfunded status at the end of the year	(117)	(127)
Assets and (liabilities) recognized on the consolidated balance sheets consist of [Abstract]
Non-current assets	0	0
Current liabilities	(8)	(8)
Non-current liabilities	(109)	(119)
Total	$ (117)	$ (127)

Pensions and Other Employee 100

Pensions and Other Employee Benefits, Net Loss and Prior Service Cost Balances in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain)	$ 896	$ 768
Prior service cost (credit)	14	0
Total amount recognized	910	768
Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain)	(12)	(10)
Prior service cost (credit)	(4)	(3)
Total amount recognized	$ (16)	$ (13)

Pensions and Other Employee 101

Pensions and Other Employee Benefits, Aggregate Accumulated Benefit Obligation in Excess of Fair Value (Details) - Pension Plans [Member] - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Aggregate accumulated benefit obligation (ABO)	$ 3,413	$ 3,120
Projected benefit obligation	3,528	3,232
Accumulated benefit obligation	3,192	2,913
Fair value of plan assets	$ 2,456	$ 2,302

Pensions and Other Employee 102

Pensions and Other Employee Benefits, Weighted Average Assumptions Used to Determine Benefit Obligations (Details)		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Pension Plans [Member]
Benefit obligations [Abstract]
Discount rate	[1]	4.41%	4.67%
Rate of compensation increase	[2]	3.50%	3.50%
U.S. Based Pension Plans [Member]
Benefit obligations [Abstract]
Rate of compensation increase		3.50%	3.50%
Assumptions used to determine net periodic benefit cost, weighted average discount rate		4.46%	4.73%
Canadian Based Pension Plans [Member]
Benefit obligations [Abstract]
Rate of compensation increase		3.50%	3.50%
Assumptions used to determine net periodic benefit cost, weighted average discount rate		3.80%	3.93%
Postretirement Benefit Plans [Member]
Benefit obligations [Abstract]
Discount rate	[3]	4.05%	4.22%
U.S. Based Postretirement Benefit Plans [Member]
Benefit obligations [Abstract]
Assumptions used to determine net periodic benefit cost, weighted average discount rate		4.11%	4.28%
Canadian Based Postretirement Benefit Plans [Member]
Benefit obligations [Abstract]
Assumptions used to determine net periodic benefit cost, weighted average discount rate		3.64%	3.74%
[1]	The weighted average discount rate assumptions used at December 31, 2016 and 2015 were comprised of separate assumptions determined by country of 4.46% and 4.73% for the U.S. based plans, respectively, and 3.80% and 3.93% for the Canadian based plans, respectively.
[2]	The weighted average rate of compensation increase assumptions were comprised of separate assumptions determined by country of 3.5% for both the U.S. based plans and Canadian based plans at December 31, 2016 and 2015.
[3]	The weighted average discount rate assumptions used at December 31, 2016 and 2015 were comprised of separate assumptions determined by country of 4.11% and 4.28% for the U.S. based plans, respectively, and 3.64% and 3.74% for the Canadian based plans, respectively.

Pensions and Other Employee 103

Pensions and Other Employee Benefits, Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Pension Plans [Member]
Components of net periodic benefit cost [Abstract]
Service cost	$ 108	$ 123	$ 106
Interest cost	135	149	147
Expected return on plan assets	(200)	(205)	(193)
Amortization of prior service cost (credits)	0	1	2
Amortization of net loss (gain)	52	68	17
Curtailment or settlement loss (gain)	2	3	1
Net periodic benefit cost	97	139	80
Postretirement Benefit Plans [Member]
Components of net periodic benefit cost [Abstract]
Service cost	2	3	3
Interest cost	6	7	8
Expected return on plan assets	(4)	(5)	(4)
Amortization of prior service cost (credits)	(2)	(2)	(2)
Amortization of net loss (gain)	(2)	0	(2)
Curtailment or settlement loss (gain)	0	0	(1)
Net periodic benefit cost	$ 0	$ 3	$ 2

Pensions and Other Employee 104

Pensions and Other Employee Benefits, Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Net loss (gain)	$ 60
Prior service cost (credit)	0
Total amount expected to be amortized	60
Pension Plans [Member]
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Net loss (gain)	179	$ (132)	$ 560
Prior service cost (credit)	15	0	1
Amortization of net (loss) gain	(52)	(68)	(17)
Amortization of prior service (cost) credit	0	(1)	(2)
Total recognized in other comprehensive income	142	(201)	542
Total recognized in net periodic benefit cost and other comprehensive income	239	(62)	622
Net loss (gain)	62
Prior service cost (credit)	1
Total amount expected to be amortized	63
Postretirement Benefit Plans [Member]
Other changes in plan assets and benefit obligations recognized in other comprehensive income [Abstract]
Net loss (gain)	(4)	(7)	5
Prior service cost (credit)	(2)	0	(1)
Amortization of net (loss) gain	2	0	2
Amortization of prior service (cost) credit	2	2	2
Total recognized in other comprehensive income	(2)	(5)	8
Total recognized in net periodic benefit cost and other comprehensive income	(2)	$ (2)	$ 10
Net loss (gain)	(2)
Prior service cost (credit)	(1)
Total amount expected to be amortized	$ (3)

Pensions and Other Employee 105

Pensions and Other Employee Benefits, Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015		Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Effect of one percentage point increase on total service and interest cost		$ 0
Effect of one percentage point decrease on total service and interest cost		0
Effect of one percentage point increase on postretirement benefit obligations		5
Effect of one percentage point decrease on postretirement benefit obligations		$ (4)
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	[1]	4.67%	4.14%		5.03%
Service cost		4.83%	0.00%	[2]	0.00%	[2]
Interest cost		3.95%	0.00%	[2]	0.00%	[2]
Expected long-term return on plan assets	[3]	7.92%	8.14%		8.13%
Rate of compensation increase	[4]	3.50%	3.50%		3.50%
Assumptions used to determine net periodic benefit cost, weighted average discount rate	[1]	4.67%	4.14%		5.03%
Assumptions used to determine net periodic benefit cost, weighted average expected long-term return on plan assets	[3]	7.92%	8.14%		8.13%
Assumptions used to determine net periodic benefit cost, Rate of compensation increase	[4]	3.50%	3.50%		3.50%
U.S. Based Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation		4.73%	4.20%		5.10%
Expected long-term return on plan assets		8.00%	8.25%
Rate of compensation increase		3.50%	3.50%		3.50%
Assumptions used to determine net periodic benefit cost, weighted average discount rate		4.73%	4.20%		5.10%
Assumptions used to determine net periodic benefit cost, weighted average expected long-term return on plan assets		8.00%	8.25%
Assumptions used to determine net periodic benefit cost, Rate of compensation increase		3.50%	3.50%		3.50%
Health care cost trend rate, covering retirees under 65 years of age in 2017		7.00%
Health care cost trend rate, covering retirees over 65 years of age in 2017		8.50%
U.S. Based Pension Plans [Member] | 2021 and Thereafter [Member]
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend rate, covering retirees under 65 years of age		5.00%
U.S. Based Pension Plans [Member] | 2024 and Thereafter [Member]
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend rate, covering retirees over 65 years of age		5.00%
Canadian Based Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation		3.93%	3.90%		4.70%
Expected long-term return on plan assets		7.25%	7.25%
Rate of compensation increase		3.50%	3.50%		3.50%
Assumptions used to determine net periodic benefit cost, weighted average discount rate		3.93%	3.90%		4.70%
Assumptions used to determine net periodic benefit cost, weighted average expected long-term return on plan assets		7.25%	7.25%
Assumptions used to determine net periodic benefit cost, Rate of compensation increase		3.50%	3.50%		3.50%
Health care cost trend in 2017		6.50%
Canadian Based Pension Plans [Member] | 2023 and Thereafter [Member]
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend		5.00%
German Based Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation		0.00%	2.20%		3.50%
Assumptions used to determine net periodic benefit cost, weighted average discount rate		0.00%	2.20%		3.50%
Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	[5]	4.22%	3.70%		4.43%
Service cost	[2]	4.37%	0.00%		0.00%
Interest cost	[2]	3.26%	0.00%		0.00%
Expected long-term return on plan assets		7.42%	7.65%		7.64%
Assumptions used to determine net periodic benefit cost, weighted average discount rate	[5]	4.22%	3.70%		4.43%
Assumptions used to determine net periodic benefit cost, weighted average expected long-term return on plan assets		7.42%	7.65%		7.64%
U.S. Based Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation		4.28%	3.70%		4.60%
Assumptions used to determine net periodic benefit cost, weighted average discount rate		4.28%	3.70%		4.60%
Canadian Based Postretirement Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation		3.74%	3.70%		4.60%
Assumptions used to determine net periodic benefit cost, weighted average discount rate		3.74%	3.70%		4.60%
[1]	The weighted average discount rate assumptions used for the years ended December 31, 2016, 2015, and 2014 were comprised of separate assumptions determined by country of 4.73%, 4.20% and 5.10% for the U.S. based plans and 3.93%, 3.90% and 4.70% for the Canadian based plans, respectively.
[2]	Not applicable as the Company changed to the spot rate approach beginning in 2016 as described above.
[3]	The weighted average expected long-term return on plan assets assumptions used were comprised of separate assumptions determined by country of 8.00% and 8.25% for the U.S. based plans for the years ended December 31, 2016 and 2015, respectively, and 7.25% for the Canadian based plans for the years ended December 31, 2016, and 2015.
[4]	The weighted average rate of compensation increase assumptions used for the years ended December 31, 2016, 2015 and 2014 were comprised of separate assumptions determined by country of 3.50% for both the U.S and Canadian based plans.
[5]	The weighted average discount rate assumptions used for the years ended December 31, 2016, 2015 and 2014 were comprised of separate assumptions determined by country of 4.28%, 3.70% and 4.40% for the U.S. based plans and 3.74%, 3.70% and 4.60% for the Canadian based plans, respectively.

Pensions and Other Employee 106

Pensions and Other Employee Benefits, Weighted Average Asset Allocations by Asset Category (Details)		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average asset allocations		100.00%	100.00%
U.S. [Member] | Domestic Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, minimum range	[1]	30.00%
Percentage of plan assets, maximum range	[1]	60.00%
Weighted-average asset allocations	[1]	55.00%	52.00%
U.S. [Member] | International Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, minimum range	[2]	10.00%
Percentage of plan assets, maximum range	[2]	20.00%
Weighted-average asset allocations	[2]	10.00%	11.00%
U.S. [Member] | Total Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, minimum range		45.00%
Percentage of plan assets, maximum range		75.00%
Weighted-average asset allocations		65.00%	63.00%
U.S. [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, minimum range		20.00%
Percentage of plan assets, maximum range		40.00%
Weighted-average asset allocations		22.00%	22.00%
U.S. [Member] | Other, Primarily Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, minimum range		0.00%
Percentage of plan assets, maximum range		15.00%
Weighted-average asset allocations		5.00%	8.00%
U.S. [Member] | Total Fixed Income Securities and Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average asset allocations		27.00%	30.00%
U.S. [Member] | Real Estate Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, minimum range		0.00%
Percentage of plan assets, maximum range		15.00%
Weighted-average asset allocations		8.00%	7.00%
Canada [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average asset allocations		100.00%	100.00%
Canada [Member] | Domestic Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average asset allocations	[1]	15.00%	13.00%
Canada [Member] | International Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average asset allocations	[2]	62.00%	62.00%
Canada [Member] | Total Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, minimum range		40.00%
Percentage of plan assets, maximum range		80.00%
Weighted-average asset allocations		77.00%	75.00%
Canada [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average asset allocations		13.00%	16.00%
Canada [Member] | Other, Primarily Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average asset allocations		10.00%	9.00%
Canada [Member] | Total Fixed Income Securities and Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, minimum range		20.00%
Percentage of plan assets, maximum range		60.00%
Weighted-average asset allocations		23.00%	25.00%
Canada [Member] | Real Estate Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Weighted-average asset allocations		0.00%	0.00%
[1]	Domestic equities for Canadian plans refers to equities of Canadian companies.
[2]	International equities for Canadian plans includes equities of U.S. companies.

Pensions and Other Employee 107

Pensions and Other Employee Benefits, Fair Value of Pension Plan Assets (Details) - USD ($) $ in Millions		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Pension Plans [Member]
Equity securities [Abstract]
Fair value of company's plan assets		$ 2,721	$ 2,552	$ 2,570
U.S. Pension Plans' Assets [Member]
Equity securities [Abstract]
Liabilities for unsettled trades, net		(23)	(30)
Fair value of company's plan assets		$ 2,421	$ 2,269
Percentage of mutual fund in total investment in fixed income - investment grade securities		62.00%	59.00%
Percentage of pooled bond funds in total investment in fixed income - investment grade securities		38.00%	41.00%
U.S. Pension Plans' Assets [Member] | U.S. Equity [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	$ 1,331	$ 1,200
U.S. Pension Plans' Assets [Member] | U.S. Equity [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	1,331	1,200
U.S. Pension Plans' Assets [Member] | U.S. Equity [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
U.S. Pension Plans' Assets [Member] | U.S. Equity [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
U.S. Pension Plans' Assets [Member] | International Equity [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	85	79
U.S. Pension Plans' Assets [Member] | International Equity [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	85	79
U.S. Pension Plans' Assets [Member] | International Equity [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
U.S. Pension Plans' Assets [Member] | International Equity [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
U.S. Pension Plans' Assets [Member] | Fixed Income - Investment Grade [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	414	400
U.S. Pension Plans' Assets [Member] | Fixed Income - Investment Grade [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	255	237
U.S. Pension Plans' Assets [Member] | Fixed Income - Investment Grade [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	159	163
U.S. Pension Plans' Assets [Member] | Fixed Income - Investment Grade [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	0	0
U.S. Pension Plans' Assets [Member] | Fixed Income - High Yield [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	136	114
U.S. Pension Plans' Assets [Member] | Fixed Income - High Yield [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
U.S. Pension Plans' Assets [Member] | Fixed Income - High Yield [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	136	114
U.S. Pension Plans' Assets [Member] | Fixed Income - High Yield [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
U.S. Pension Plans' Assets [Member] | Real Estate Investment Trusts [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	193	170
U.S. Pension Plans' Assets [Member] | Real Estate Investment Trusts [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	193	170
U.S. Pension Plans' Assets [Member] | Real Estate Investment Trusts [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	0	0
U.S. Pension Plans' Assets [Member] | Real Estate Investment Trusts [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	0	0
U.S. Pension Plans' Assets [Member] | Other [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	114	166
U.S. Pension Plans' Assets [Member] | Other [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	0	0
U.S. Pension Plans' Assets [Member] | Other [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	114	166
U.S. Pension Plans' Assets [Member] | Other [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	0	0
U.S. Pension Plans' Assets [Member] | Total Assets at Fair Value [Member]
Equity securities [Abstract]
Fair value of company's plan assets		2,273	2,129
U.S. Pension Plans' Assets [Member] | Total Assets at Fair Value [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		1,864	1,686
U.S. Pension Plans' Assets [Member] | Total Assets at Fair Value [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		409	443
U.S. Pension Plans' Assets [Member] | Total Assets at Fair Value [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		0	0
U.S. Pension Plans' Assets [Member] | Other Investments Measured at Net Asset Value [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[6],[7]	171	170
Canadian Pension Plans' Assets [Member]
Equity securities [Abstract]
Liabilities for unsettled trades, net		0	0
Fair value of company's plan assets		300	283
Canadian Pension Plans' Assets [Member] | U.S. Equity [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	79	73
Canadian Pension Plans' Assets [Member] | U.S. Equity [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	79	73
Canadian Pension Plans' Assets [Member] | U.S. Equity [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
Canadian Pension Plans' Assets [Member] | U.S. Equity [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
Canadian Pension Plans' Assets [Member] | International Equity [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	104	91
Canadian Pension Plans' Assets [Member] | International Equity [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	104	91
Canadian Pension Plans' Assets [Member] | International Equity [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
Canadian Pension Plans' Assets [Member] | International Equity [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
Canadian Pension Plans' Assets [Member] | Fixed Income - Investment Grade [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	0	0
Canadian Pension Plans' Assets [Member] | Fixed Income - Investment Grade [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	0	0
Canadian Pension Plans' Assets [Member] | Fixed Income - Investment Grade [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	0	0
Canadian Pension Plans' Assets [Member] | Fixed Income - Investment Grade [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	0	0
Canadian Pension Plans' Assets [Member] | Fixed Income - High Yield [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
Canadian Pension Plans' Assets [Member] | Fixed Income - High Yield [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
Canadian Pension Plans' Assets [Member] | Fixed Income - High Yield [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
Canadian Pension Plans' Assets [Member] | Fixed Income - High Yield [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
Canadian Pension Plans' Assets [Member] | Real Estate Investment Trusts [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	0	0
Canadian Pension Plans' Assets [Member] | Real Estate Investment Trusts [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	0	0
Canadian Pension Plans' Assets [Member] | Real Estate Investment Trusts [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	0	0
Canadian Pension Plans' Assets [Member] | Real Estate Investment Trusts [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	0	0
Canadian Pension Plans' Assets [Member] | Other [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	32	27
Canadian Pension Plans' Assets [Member] | Other [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	5	6
Canadian Pension Plans' Assets [Member] | Other [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	27	21
Canadian Pension Plans' Assets [Member] | Other [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	0	0
Canadian Pension Plans' Assets [Member] | Total Assets at Fair Value [Member]
Equity securities [Abstract]
Fair value of company's plan assets		215	191
Canadian Pension Plans' Assets [Member] | Total Assets at Fair Value [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		188	170
Canadian Pension Plans' Assets [Member] | Total Assets at Fair Value [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		27	21
Canadian Pension Plans' Assets [Member] | Total Assets at Fair Value [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		0	0
Canadian Pension Plans' Assets [Member] | Other Investments Measured at Net Asset Value [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[6],[7]	$ 85	$ 92
Percentage of mutual fund investment in equity trust funds		55.00%	52.00%
Percentage of pooled bond fund investment in equity trust funds		45.00%	48.00%
Postretirement Benefit Plans [Member]
Equity securities [Abstract]
Fair value of company's plan assets		$ 60	$ 57	$ 60
Percentage of mutual fund in total investment in fixed income - investment grade securities		73.00%	73.00%
Percentage of pooled bond funds in total investment in fixed income - investment grade securities		27.00%	27.00%
Postretirement Benefit Plans [Member] | U.S. Equity [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[8]	$ 37	$ 35
Postretirement Benefit Plans [Member] | U.S. Equity [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[8]	37	35
Postretirement Benefit Plans [Member] | U.S. Equity [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[8]	0	0
Postretirement Benefit Plans [Member] | U.S. Equity [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[8]	0	0
Postretirement Benefit Plans [Member] | International Equity [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[8]	1	1
Postretirement Benefit Plans [Member] | International Equity [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[8]	1	1
Postretirement Benefit Plans [Member] | International Equity [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[8]	0	0
Postretirement Benefit Plans [Member] | International Equity [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[8]	0	0
Postretirement Benefit Plans [Member] | Fixed Income - Investment Grade [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[9]	11	11
Postretirement Benefit Plans [Member] | Fixed Income - Investment Grade [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[9]	8	8
Postretirement Benefit Plans [Member] | Fixed Income - Investment Grade [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[9]	3	3
Postretirement Benefit Plans [Member] | Fixed Income - Investment Grade [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[9]	0	0
Postretirement Benefit Plans [Member] | Fixed Income - High Yield [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	2	2
Postretirement Benefit Plans [Member] | Fixed Income - High Yield [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
Postretirement Benefit Plans [Member] | Fixed Income - High Yield [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	2	2
Postretirement Benefit Plans [Member] | Fixed Income - High Yield [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
Postretirement Benefit Plans [Member] | Real Estate Investment Trusts [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[10]	3	3
Postretirement Benefit Plans [Member] | Real Estate Investment Trusts [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[10]	3	3
Postretirement Benefit Plans [Member] | Real Estate Investment Trusts [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[10]	0	0
Postretirement Benefit Plans [Member] | Real Estate Investment Trusts [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[10]	0	0
Postretirement Benefit Plans [Member] | Other [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[11]	3	2
Postretirement Benefit Plans [Member] | Other [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[11]	0	0
Postretirement Benefit Plans [Member] | Other [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[11]	3	2
Postretirement Benefit Plans [Member] | Other [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[11]	0	0
Postretirement Benefit Plans [Member] | Total Assets at Fair Value [Member]
Equity securities [Abstract]
Fair value of company's plan assets		57	54
Postretirement Benefit Plans [Member] | Total Assets at Fair Value [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		49	47
Postretirement Benefit Plans [Member] | Total Assets at Fair Value [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		8	7
Postretirement Benefit Plans [Member] | Total Assets at Fair Value [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		0	0
Postretirement Benefit Plans [Member] | Other Investments Measured at Net Asset Value [Member]
Equity securities [Abstract]
Liabilities for unsettled trades, net	[12],[13]	$ 3	$ 3
[1]	Equity securities consist of investments in common stock of U.S. and international companies. The fair value of equity securities is based on quoted market prices available in active markets at the close of a trading day, primarily the New York Stock Exchange (NYSE), National Association of Securities Dealers Automated Quotations (NASDAQ), and various international exchanges.
[2]	Approximately 62% and 59% at December 31, 2016 and 2015, respectively, of U.S. plan assets that are invested in the Fixed Income - Investment Grade asset category consist of a mutual fund offered by a registered investment company (the Fund) and fixed income securities. The Fund invests in investment grade fixed income securities, mortgaged-backed securities, U.S. treasury and agency bonds and corporate bonds. These investments are classified by the Company as a Level 1 measurement within the fair value hierarchy, as the mutual fund trades on an active market and daily, quoted prices are available. The remaining 38% and 41% at December 31, 2016 and 2015, respectively, of U.S. plan assets are fixed income securities, primarily investment grade corporate bonds from various industries held directly by the plan. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs and are classified as Level 2.
[3]	Fixed Income - High Yield consists of investments in corporate high-yield bonds from various industries. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs.
[4]	Real Estate Investment Trusts (REITs) consist of securities that trade on the major exchanges and invest directly in real estate, either through properties or mortgages.
[5]	Other consists primarily of: (1) money market accounts, which invest primarily in short-term, high quality money market securities such as government obligations, commercial paper, time deposits and certificates of deposit, and are classified as Level 2, and (2) cash, which is classified as Level 1.
[6]	All of the U.S. plans other investments measured using NAV at December 31, 2016 and 2015 and approximately 55% and 52% at December 31, 2016 and 2015, respectively, of the Canadian plans other investments measured using NAV consist of a regulated commingled equity trust fund, for which fair value is based on the NAV at the end of each month. The NAV is calculated by the fund manager based on the fair value of the fund's holdings, primarily equity securities traded in active markets, determined as of the end of each month as a practical expedient to estimating fair value. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Withdrawals are permitted, with notice by the 20th day of each month, based on NAV. Approximately 45% and 48% at December 31, 2016 and 2015, respectively, of the Canadian plans other investments measured using NAV are invested in regulated commingled bond funds (the "Bond Funds"). As these Bond Funds do not trade in an active market, the fair value is based on NAVs calculated by fund managers based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs as a practical expedient to estimating fair value and classified as Level 2. Withdrawals are permitted monthly, with notice between 0 and 3 days of the transaction date, based on NAV.
[7]	In accordance with ASU 2015-07, certain investments that are measured at fair value using the net asset value (NAV) per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statements of financial position.
[8]	Equity securities consist of investments in common stock of U.S. and international companies. The fair value of equity securities is based on quoted market prices available in active markets at the close of a trading day, primarily the NYSE, NASDAQ, and various international exchanges.
[9]	Approximately 73% at December 31, 2016 and 2015 of the postretirement benefit plan assets that are invested in the Fixed Income - Investment Grade asset category consist of the Fund and fixed income securities. The Fund invests in investment grade fixed income securities, mortgaged-backed securities, U.S. treasury and agency bonds and corporate bonds. These investments are classified by the Company as a Level 1 measurement within the fair value hierarchy as the mutual fund trades on an active market and daily, quoted prices are available. The remaining 27% at December 31, 2016 and 2015 of the postretirement benefit plan assets are fixed income securities, primarily investment grade corporate bonds from various industries held directly by the plan. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs and are classified as Level 2.
[10]	REITs consist of securities that trade on the major exchanges and invest directly, either through properties or mortgages.
[11]	Other consists primarily of money market accounts, which invest primarily in short-term, high quality money market securities such as government obligations, commercial paper, time deposits and certificates of deposit.
[12]	All of the postretirement benefit plans other investments measured using NAV at December 31, 2016 and 2015 consist of a regulated commingled equity trust fund, which fair value is based on NAV at the end of each month. The NAV is calculated by the fund manager based on the fair value of the fund's holdings, primarily equity securities traded in active markets, determined as of the end of each month as a practical expedient to estimating fair value. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Withdrawals are permitted, with notice by the 20th day of each month, based on NAV.
[13]	In accordance with ASU 2015-07, certain investments that are measured at fair value using the NAV per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statements of financial position.

Pensions and Other Employee 108

Pensions and Other Employee Benefits, Fair Value of Postretirement Benefit Plans Assets (Details) - USD ($) $ in Millions		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Pension Plans [Member]
Equity securities [Abstract]
Fair value of company's plan assets		$ 2,721	$ 2,552	$ 2,570
Postretirement Benefit Plans [Member]
Equity securities [Abstract]
Fair value of company's plan assets		$ 60	$ 57	$ 60
Percentage of mutual fund in total investment in fixed income - investment grade securities		73.00%	73.00%
Percentage of pooled bond funds in total investment in fixed income - investment grade securities		27.00%	27.00%
Postretirement Benefit Plans [Member] | U.S. Equity [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	$ 37	$ 35
Postretirement Benefit Plans [Member] | U.S. Equity [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	37	35
Postretirement Benefit Plans [Member] | U.S. Equity [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
Postretirement Benefit Plans [Member] | U.S. Equity [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
Postretirement Benefit Plans [Member] | International Equity [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	1	1
Postretirement Benefit Plans [Member] | International Equity [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	1	1
Postretirement Benefit Plans [Member] | International Equity [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
Postretirement Benefit Plans [Member] | International Equity [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[1]	0	0
Postretirement Benefit Plans [Member] | Fixed Income - Investment Grade [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	11	11
Postretirement Benefit Plans [Member] | Fixed Income - Investment Grade [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	8	8
Postretirement Benefit Plans [Member] | Fixed Income - Investment Grade [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	3	3
Postretirement Benefit Plans [Member] | Fixed Income - Investment Grade [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[2]	0	0
Postretirement Benefit Plans [Member] | Fixed Income - High Yield [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	2	2
Postretirement Benefit Plans [Member] | Fixed Income - High Yield [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
Postretirement Benefit Plans [Member] | Fixed Income - High Yield [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	2	2
Postretirement Benefit Plans [Member] | Fixed Income - High Yield [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[3]	0	0
Postretirement Benefit Plans [Member] | Real Estate Investment Trusts [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	3	3
Postretirement Benefit Plans [Member] | Real Estate Investment Trusts [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	3	3
Postretirement Benefit Plans [Member] | Real Estate Investment Trusts [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	0	0
Postretirement Benefit Plans [Member] | Real Estate Investment Trusts [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[4]	0	0
Postretirement Benefit Plans [Member] | Other Plan Assets [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	3	2
Postretirement Benefit Plans [Member] | Other Plan Assets [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	0	0
Postretirement Benefit Plans [Member] | Other Plan Assets [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	3	2
Postretirement Benefit Plans [Member] | Other Plan Assets [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets	[5]	0	0
Postretirement Benefit Plans [Member] | Total Assets at Fair Value [Member]
Equity securities [Abstract]
Fair value of company's plan assets		57	54
Postretirement Benefit Plans [Member] | Total Assets at Fair Value [Member] | Level 1 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		49	47
Postretirement Benefit Plans [Member] | Total Assets at Fair Value [Member] | Level 2 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		8	7
Postretirement Benefit Plans [Member] | Total Assets at Fair Value [Member] | Level 3 [Member]
Equity securities [Abstract]
Fair value of company's plan assets		0	0
Postretirement Benefit Plans [Member] | Other Investments Measured at Net Asset Value [Member]
Equity securities [Abstract]
Liabilities for unsettled trades, net	[6],[7]	$ 3	$ 3
[1]	Equity securities consist of investments in common stock of U.S. and international companies. The fair value of equity securities is based on quoted market prices available in active markets at the close of a trading day, primarily the NYSE, NASDAQ, and various international exchanges.
[2]	Approximately 73% at December 31, 2016 and 2015 of the postretirement benefit plan assets that are invested in the Fixed Income - Investment Grade asset category consist of the Fund and fixed income securities. The Fund invests in investment grade fixed income securities, mortgaged-backed securities, U.S. treasury and agency bonds and corporate bonds. These investments are classified by the Company as a Level 1 measurement within the fair value hierarchy as the mutual fund trades on an active market and daily, quoted prices are available. The remaining 27% at December 31, 2016 and 2015 of the postretirement benefit plan assets are fixed income securities, primarily investment grade corporate bonds from various industries held directly by the plan. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs and are classified as Level 2.
[3]	Fixed Income - High Yield consists of investments in corporate high-yield bonds from various industries. The fair values of these investments are based on yields currently available on comparable bonds of issuers with similar credit ratings, quoted prices of similar bonds in an active market, or cash flows based on observable inputs.
[4]	REITs consist of securities that trade on the major exchanges and invest directly, either through properties or mortgages.
[5]	Other consists primarily of money market accounts, which invest primarily in short-term, high quality money market securities such as government obligations, commercial paper, time deposits and certificates of deposit.
[6]	All of the postretirement benefit plans other investments measured using NAV at December 31, 2016 and 2015 consist of a regulated commingled equity trust fund, which fair value is based on NAV at the end of each month. The NAV is calculated by the fund manager based on the fair value of the fund's holdings, primarily equity securities traded in active markets, determined as of the end of each month as a practical expedient to estimating fair value. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Withdrawals are permitted, with notice by the 20th day of each month, based on NAV.
[7]	In accordance with ASU 2015-07, certain investments that are measured at fair value using the NAV per share (or its equivalent) practical expedient have not been classified in the fair value hierarchy. The fair value amounts presented in this table are intended to permit reconciliation of the fair value hierarchy to the amounts presented in the statements of financial position.

Pensions and Other Employee 109

Pensions and Other Employee Benefits, Contributions (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to plans in 2017	$ 100
Postretirement Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions to plans in 2017	$ 10

Pensions and Other Employee 110

Pensions and Other Employee Benefits, Estimated Future Benefit Payments (Details) $ in Millions	Dec. 31, 2016USD ($)
Pension Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2,017	$ 162
2,018	156
2,019	162
2,020	171
2,021	175
Years 2022-2026	1,201
Postretirement Benefit Plans [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2,017	13
2,018	13
2,019	14
2,020	14
2,021	14
Years 2022-2026	65
Subsidy Receipts, 2017	0
Subsidy Receipts, 2018	0
Subsidy Receipts, 2019	0
Subsidy Receipts, 2020	0
Subsidy Receipts, 2021	0
Subsidy Receipts, Years 2022-2026	$ 1

Pensions and Other Employee 111

Pensions and Other Employee Benefits, Employee Savings Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Continuing Operations [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's matching contributions in L-3 Holdings' common stock and cash	$ 118	$ 131	$ 135
Discontinued Operations [Member]
Defined Benefit Plan Disclosure [Line Items]
Company's matching contributions in L-3 Holdings' common stock and cash	$ 1	$ 12	$ 11

Pensions and Other Employee 112

Pensions and Other Employee Benefits, Multi-Employer Benefit Plans (Details) $ in Millions		12 Months Ended
		Dec. 31, 2016USD ($)PensionFunds		Dec. 31, 2015USD ($)		Dec. 31, 2014USD ($)
Multiemployer Plans [Line Items]
Contributions by L-3 Communications		$ 26		$ 23		$ 19
Minimum percentage funded to have green zone status rating		80.00%
Percentage of total plan contributions				5.00%		5.00%
Percentage of contributions from reportable segment		63.00%
Expiration date of multiple bargaining agreements		Apr. 28, 2019
Number of pension funds included in Other Pension Funds | PensionFunds		3
IAM National Pension Fund [Member]
Multiemployer Plans [Line Items]
Contributions by L-3 Communications		$ 26	[1]	$ 23	[2]	$ 19	[2]
EIN/Pension Plan Number		51-6031295/002
Pension Protection Act Zone Status	[3]	Green		Green
FIP/RP Status Pending/Implemented	[4]	No
Surcharge Imposed		No
Expiration Date of Collective-Bargaining Agreement, First		Apr. 9, 2017
Expiration Date of Collective-Bargaining Agreement, Last	[5]	Jun. 28, 2019
Other Pension Funds [Member]
Multiemployer Plans [Line Items]
Contributions by L-3 Communications	[6]	$ 0		$ 0		$ 0
[1]	At the date the audited financial statements for the Company were issued, the Form 5500 for the plan year ended December 31, 2016 was not available.
[2]	Represents [5%] of total plan contributions for the years ended December 31, 2015 and 2014 based on Form 5500.
[3]	A zone status rating of green indicates the plan is at least 80% funded.
[4]	Funding improvement plan or rehabilitation plan.
[5]	The Company is a party to multiple bargaining agreements for multiple projects that require contributions into the IAM National Pension Fund. The most significant of these agreements, expiring April 28, 2019, covers multiple programs in the Company's Aerospace Systems reportable segment and represents 63% of 2016 contributions.
[6]	Consists of three pension funds in which the Company's contributions are individually, and in the aggregate, insignificant.

Supplemental Cash Flow Infor113

Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Cash Flow Information [Abstract]
Interest paid on outstanding debt	$ 162	$ 182	$ 176
Income tax payments	120	132	129
Income tax refunds	$ 8	$ 8	$ 9

Segment Information, Products a

Segment Information, Products and Services (Details) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2016USD ($)	Sep. 23, 2016USD ($)	Jun. 24, 2016USD ($)	Mar. 25, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 25, 2015USD ($)	Jun. 26, 2015USD ($)	Mar. 27, 2015USD ($)	Dec. 31, 2016USD ($)Segment	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Segment Information [Abstract]
Number of reportable segments | Segment										3
Corporate expenses											$ 15	$ 16
Net Sales [Abstract]
Products										$ 6,442	6,589	6,839
Services										4,069	3,877	4,147
Total net sales		$ 2,989	$ 2,505	$ 2,664	$ 2,353	$ 2,871	$ 2,564	$ 2,543	$ 2,488	10,511	10,466	10,986
Operating income [Abstract]
Operating income		294	$ 215	$ 247	$ 252	(96)	$ 231	$ 153	$ 187	1,008	475	1,012
Loss related to business divestitures	[1]									0	(31)	0
Goodwill impairment charges	[2]									0	(384)	0
Depreciation and amortization [Abstract]
Depreciation and amortization										206	210	214
Capital Expenditures [Abstract]
Capital Expenditures										216	197	174
Total Assets [Abstract]
Total Assets		11,865				12,069				11,865	12,069	13,692
Assets held for sale		0				0				0	0	547
Assets of discontinued operations		0				664				0	664	1,262
Continuing Operations [Member]
Operating income [Abstract]
Goodwill impairment charges											(384)
NSS Including Business Retained [Member] | Continuing Operations [Member]
Operating income [Abstract]
Goodwill impairment charges											(46)
NSS [Member]
Operating income [Abstract]
Goodwill impairment charges											(608)
NSS [Member] | Continuing Operations [Member]
Operating income [Abstract]
Goodwill impairment charges											(37)
Business Retained from NSS [Member] | Continuing Operations [Member]
Operating income [Abstract]
Goodwill impairment charges											(9)
Vertex Aerospace [Member]
Operating income [Abstract]
Goodwill impairment charges											(338)
Vertex Aerospace [Member] | Continuing Operations [Member]
Operating income [Abstract]
Goodwill impairment charges											(338)
Electronic Systems [Member]
Operating income [Abstract]
Goodwill impairment charges											(26)
Aerospace Systems [Member]
Operating income [Abstract]
Goodwill impairment charges											(338)
Communication Systems [Member]
Operating income [Abstract]
Goodwill impairment charges											(20)
Operating Segments [Member]
Operating income [Abstract]
Operating income										1,008	890	1,012
Operating Segments [Member] | Electronic Systems [Member]
Net Sales [Abstract]
Products										3,293	3,390	3,685
Services										1,042	999	1,057
Operating income [Abstract]
Operating income										518	489	533
Depreciation and amortization [Abstract]
Depreciation and amortization										105	110	123
Capital Expenditures [Abstract]
Capital Expenditures										113	99	80
Total Assets [Abstract]
Total Assets		6,802				6,426				6,802	6,426	6,281
Operating Segments [Member] | Aerospace Systems [Member]
Net Sales [Abstract]
Products										1,662	1,661	1,722
Services										2,580	2,503	2,604
Operating income [Abstract]
Operating income										289	205	283
Depreciation and amortization [Abstract]
Depreciation and amortization										54	50	40
Capital Expenditures [Abstract]
Capital Expenditures										56	55	59
Total Assets [Abstract]
Total Assets		2,535				2,630				2,535	2,630	3,011
Operating Segments [Member] | Communication Systems [Member]
Net Sales [Abstract]
Products										1,585	1,648	1,546
Services										488	441	539
Operating income [Abstract]
Operating income										201	196	196
Depreciation and amortization [Abstract]
Depreciation and amortization										47	50	51
Capital Expenditures [Abstract]
Capital Expenditures										37	37	29
Total Assets [Abstract]
Total Assets		2,031				1,984				2,031	1,984	2,025
Corporate [Member]
Capital Expenditures [Abstract]
Capital Expenditures										10	6	6
Total Assets [Abstract]
Total Assets		$ 497				$ 365				497	365	566
Elimination of Intercompany Sales [Member]
Net Sales [Abstract]
Products										(98)	(110)	(114)
Services										$ (41)	$ (66)	$ (53)
[1]	See Note 3 for information regarding the Company's business divestitures.
[2]	Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information.

Segment Information, Geographic

Segment Information, Geographic Location (Details) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2016	Sep. 23, 2016	Jun. 24, 2016	Mar. 25, 2016	Dec. 31, 2015	Sep. 25, 2015	Jun. 26, 2015	Mar. 27, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Property, plant and equipment, net		$ 1,121				$ 1,097				$ 1,121	$ 1,097
Net sales		2,989	$ 2,505	$ 2,664	$ 2,353	2,871	$ 2,564	$ 2,543	$ 2,488	10,511	10,466	$ 10,986
U.S. Government Agencies [Member]
Segment Reporting Information [Line Items]
Net sales	[1]									7,649	7,291	7,464
Commercial [Member]
Segment Reporting Information [Line Items]
Net sales										1,282	1,376	1,656
Foreign Governments [Member]
Segment Reporting Information [Line Items]
Net sales	[1]									1,580	1,799	1,866
Reportable Geographical Components [Member] | United States [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net		974				971				974	971
Net sales										8,199	7,908	8,051
Reportable Geographical Components [Member] | United Kingdom [Member]
Segment Reporting Information [Line Items]
Net sales										331	336	335
Reportable Geographical Components [Member] | Australia [Member]
Segment Reporting Information [Line Items]
Net sales										254	321	254
Reportable Geographical Components [Member] | Canada [Member]
Segment Reporting Information [Line Items]
Net sales										297	281	289
Reportable Geographical Components [Member] | South Korea [Member]
Segment Reporting Information [Line Items]
Net sales										127	207	226
Reportable Geographical Components [Member] | Saudi Arabia (Member)
Segment Reporting Information [Line Items]
Net sales										159	201	160
Reportable Geographical Components [Member] | Japan [Member]
Segment Reporting Information [Line Items]
Net sales										81	95	124
Reportable Geographical Components [Member] | France
Segment Reporting Information [Line Items]
Net sales										75	62	74
Reportable Geographical Components [Member] | Other [Member]
Segment Reporting Information [Line Items]
Property, plant and equipment, net		$ 147				$ 126				147	126
Net sales										988	1,055	1,473
Reportable Geographical Components [Member] | Total International [Member]
Segment Reporting Information [Line Items]
Net sales										$ 2,312	$ 2,558	$ 2,935
[1]	Includes sales for which the Company is the prime contractor as well as sales based on the ultimate end customer for which the Company is a subcontractor.

Employee Severance and Termi116

Employee Severance and Termination Costs (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)Employees	Dec. 31, 2015USD ($)Employees	Dec. 31, 2014USD ($)Employees
Restructuring Cost and Reserve [Line Items]
Employee severance and other termination costs	$ 17	$ 18	$ 29
Number of employees terminated | Employees	700	800	1,800
Remaining balance of employee termination costs	$ 9
Electronic Systems [Member]
Restructuring Cost and Reserve [Line Items]
Employee severance and other termination costs	8	$ 8	$ 16
Aerospace Systems [Member]
Restructuring Cost and Reserve [Line Items]
Employee severance and other termination costs	2	4	5
Communication Systems [Member]
Restructuring Cost and Reserve [Line Items]
Employee severance and other termination costs	$ 7	6	$ 8
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Payments for employee termination costs		$ 9

Unaudited Quarterly Financia117

Unaudited Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended																12 Months Ended
	Dec. 31, 2016		Sep. 23, 2016		Jun. 24, 2016		Mar. 25, 2016		Dec. 31, 2015		Sep. 25, 2015		Jun. 26, 2015		Mar. 27, 2015		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Unaudited Quarterly Financial Data [Abstract]
Sales	$ 2,989		$ 2,505		$ 2,664		$ 2,353		$ 2,871		$ 2,564		$ 2,543		$ 2,488		$ 10,511	$ 10,466	$ 10,986
Operating income (loss)	294		215		247		252		(96)		231		153		187		1,008	475	1,012
Income (loss) from continuing operations	192		151		151		167		(56)		128		120		105		661	297	645
Net income (loss)	192		151		151		230		(162)		(296)		124		109		724	(225)	677
Net income (loss) attributable to L3	$ 188		$ 148		$ 147		$ 227		$ (166)		$ (299)		$ 120		$ 105		$ 710	$ (240)	$ 664
Basic earnings (loss) per share from continuing operations (in dollars per share)	$ 2.43	[1]	$ 1.91	[1]	$ 1.90	[1]	$ 2.11	[1]	$ (0.76)	[1]	$ 1.56	[1]	$ 1.41	[1]	$ 1.23	[1]	$ 8.36	$ 3.49	$ 7.40
Basic earnings (loss) per share (in dollars per share)	2.43	[1]	1.91	[1]	1.90	[1]	2.92	[1]	(2.11)	[1]	(3.74)	[1]	1.46	[1]	1.28	[1]	9.17	(2.97)	7.78
Diluted earnings (loss) per share from continuing operations (in dollars per share)	2.38	[1]	1.88	[1]	1.88	[1]	2.08	[1]	(0.76)	[1]	1.54	[1]	1.39	[1]	1.20	[1]	8.21	3.44	7.20
Diluted earnings (loss) per share (in dollars per share)	$ 2.38	[1]	$ 1.88	[1]	$ 1.88	[1]	$ 2.87	[1]	$ (2.11)	[1]	$ (3.68)	[1]	$ 1.44	[1]	$ 1.25	[1]	$ 9.01	$ (2.93)	$ 7.56
[1]	EPS in each quarter is computed using the weighted-average number of shares outstanding during that quarter, while EPS for the full year is computed using the weighted-average number of shares outstanding during the year. Therefore, the sum of the four quarters' EPS may not equal the full year computed EPS.

Financial Information of L3 118

Financial Information of L3 and Its Subsidiaries, Condensed Combining Balance Sheets (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 363	$ 207	$ 442	$ 500
Billed receivables, net	731	746
Contracts in process	2,055	2,081
Other current assets	548	534
Assets of discontinued operations	0	664	1,262
Total current assets	3,697	4,232
Goodwill	6,560	6,281	6,512
Other assets	1,608	1,556
Investment in and amounts due from consolidated subsidiaries	0	0
Total assets	11,865	12,069	13,692
Current portion of long-term debt	0	499
Current liabilities	2,135	2,160
Liabilities of discontinued operations	0	220
Amounts due to consolidated subsidiaries	0
Other long-term liabilities	1,781	1,634
Long-term debt	3,325	3,127
Total liabilities	7,241	7,640
L3 shareholders' equity	4,553	4,355
Noncontrolling interests	71	74
Total equity	4,624	4,429	5,360	6,056
Total liabilities and equity	11,865	12,069
L3 [Member]
Current assets:
Cash and cash equivalents	291	137	361	258
Billed receivables, net	261	278
Contracts in process	694	872
Other current assets	236	288
Assets of discontinued operations		0
Total current assets	1,482	1,575
Goodwill	2,162	2,318
Other assets	705	800
Investment in and amounts due from consolidated subsidiaries	5,867	5,609
Total assets	10,216	10,302
Current portion of long-term debt	0	499
Current liabilities	789	911
Liabilities of discontinued operations		0
Amounts due to consolidated subsidiaries	0
Other long-term liabilities	1,549	1,410
Long-term debt	3,325	3,127
Total liabilities	5,663	5,947
L3 shareholders' equity	4,553	4,355
Noncontrolling interests	0	0
Total equity	4,553	4,355
Total liabilities and equity	10,216	10,302
Guarantor Subsidiaries [Member]
Current assets:
Cash and cash equivalents	1	0	1	0
Billed receivables, net	285	297
Contracts in process	1,125	958
Other current assets	187	137
Assets of discontinued operations		664
Total current assets	1,598	2,056
Goodwill	3,227	2,973
Other assets	591	496
Investment in and amounts due from consolidated subsidiaries	5,430	3,739
Total assets	10,846	9,264
Current portion of long-term debt		0
Current liabilities	1,022	899
Liabilities of discontinued operations		220
Amounts due to consolidated subsidiaries	0
Other long-term liabilities	200	195
Long-term debt	0	0
Total liabilities	1,222	1,314
L3 shareholders' equity	9,624	7,950
Noncontrolling interests	0	0
Total equity	9,624	7,950
Total liabilities and equity	10,846	9,264
Non-Guarantor Subsidiaries [Member]
Current assets:
Cash and cash equivalents	207	165	142	261
Billed receivables, net	185	171
Contracts in process	236	251
Other current assets	125	109
Assets of discontinued operations		0
Total current assets	753	696
Goodwill	1,171	990
Other assets	312	260
Investment in and amounts due from consolidated subsidiaries	0	111
Total assets	2,236	2,057
Current portion of long-term debt		0
Current liabilities	460	445
Liabilities of discontinued operations		0
Amounts due to consolidated subsidiaries	282
Other long-term liabilities	32	29
Long-term debt	0	0
Total liabilities	774	474
L3 shareholders' equity	1,462	1,583
Noncontrolling interests	0	0
Total equity	1,462	1,583
Total liabilities and equity	2,236	2,057
Eliminations [Member]
Current assets:
Cash and cash equivalents	(136)	(95)	$ (62)	$ (19)
Billed receivables, net	0	0
Contracts in process	0	0
Other current assets	0	0
Assets of discontinued operations		0
Total current assets	(136)	(95)
Goodwill	0	0
Other assets	0	0
Investment in and amounts due from consolidated subsidiaries	(11,297)	(9,459)
Total assets	(11,433)	(9,554)
Current portion of long-term debt		0
Current liabilities	(136)	(95)
Liabilities of discontinued operations		0
Amounts due to consolidated subsidiaries	(282)
Other long-term liabilities	0	0
Long-term debt	0	0
Total liabilities	(418)	(95)
L3 shareholders' equity	(11,086)	(9,533)
Noncontrolling interests	71	74
Total equity	(11,015)	(9,459)
Total liabilities and equity	$ (11,433)	$ (9,554)

Financial Information of L3 119

Financial Information of L3 and Its Subsidiaries, Condensed Combining Statements of Operations (Details) - USD ($) $ in Millions		3 Months Ended								12 Months Ended
		Dec. 31, 2016	Sep. 23, 2016	Jun. 24, 2016	Mar. 25, 2016	Dec. 31, 2015	Sep. 25, 2015	Jun. 26, 2015	Mar. 27, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Total net sales		$ 2,989	$ 2,505	$ 2,664	$ 2,353	$ 2,871	$ 2,564	$ 2,543	$ 2,488	$ 10,511	$ 10,466	$ 10,986
Total cost of sales										(9,503)	(9,576)	(9,974)
(Loss) gain related to business divestitures	[1]									0	(31)	0
Impairment charge	[2]									0	(384)	0
Operating income (loss)		294	215	247	252	(96)	231	153	187	1,008	475	1,012
Interest expense										(169)	(169)	(158)
Interest and other income, net										18	17	18
Debt retirement charge										(7)	(1)	0
Income (loss) from continuing operations before income taxes										850	322	872
(Provision) benefit for income taxes										(189)	(25)	(227)
Equity in net income of consolidated subsidiaries										0	0	0
Income from continuing operations		192	151	151	167	(56)	128	120	105	661	297	645
Income from discontinued operations, net of income tax										63	(522)	32
Net (loss) income		192	151	151	230	(162)	(296)	124	109	724	(225)	677
Net income attributable to noncontrolling interests										(14)	(15)	(13)
Net income (loss) attributable to L3		$ 188	$ 148	$ 147	$ 227	$ (166)	$ (299)	$ 120	$ 105	710	(240)	664
Comprehensive (loss) income attributable to L3										558	(230)	190
L3 [Member]
Condensed Financial Statements, Captions [Line Items]
Total net sales										3,388	3,580	3,586
Total cost of sales										(3,078)	(3,283)	(3,255)
(Loss) gain related to business divestitures											(13)
Impairment charge											0
Operating income (loss)										310	284	331
Interest expense										(168)	(167)	(156)
Interest and other income, net										11	16	15
Debt retirement charge										(7)	(1)
Income (loss) from continuing operations before income taxes										146	132	190
(Provision) benefit for income taxes										(32)	(10)	(49)
Equity in net income of consolidated subsidiaries										596	(362)	523
Income from continuing operations										710	(240)	664
Income from discontinued operations, net of income tax										0	0	0
Net (loss) income										710	(240)	664
Net income attributable to noncontrolling interests										0	0	0
Net income (loss) attributable to L3										710	(240)	664
Comprehensive (loss) income attributable to L3										558	(230)	190
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total net sales										6,063	5,265	5,460
Total cost of sales										(5,610)	(4,906)	(5,017)
(Loss) gain related to business divestitures											(31)
Impairment charge											(364)
Operating income (loss)										453	(36)	443
Interest expense										(1)	(1)	(2)
Interest and other income, net										1	0	0
Debt retirement charge										0	0
Income (loss) from continuing operations before income taxes										453	(37)	441
(Provision) benefit for income taxes										(101)	3	(115)
Equity in net income of consolidated subsidiaries										0	0	0
Income from continuing operations										352	(34)	326
Income from discontinued operations, net of income tax										63	(522)	32
Net (loss) income										415	(556)	358
Net income attributable to noncontrolling interests										0	0	0
Net income (loss) attributable to L3										415	(556)	358
Comprehensive (loss) income attributable to L3										425	(560)	356
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Total net sales										1,379	1,935	2,218
Total cost of sales										(1,134)	(1,701)	(1,980)
(Loss) gain related to business divestitures											13
Impairment charge											(20)
Operating income (loss)										245	227	238
Interest expense										0	(1)	0
Interest and other income, net										6	1	3
Debt retirement charge										0	0
Income (loss) from continuing operations before income taxes										251	227	241
(Provision) benefit for income taxes										(56)	(18)	(63)
Equity in net income of consolidated subsidiaries										0	0	0
Income from continuing operations										195	209	178
Income from discontinued operations, net of income tax										0	0	0
Net (loss) income										195	209	178
Net income attributable to noncontrolling interests										0	0	0
Net income (loss) attributable to L3										195	209	178
Comprehensive (loss) income attributable to L3										118	98	47
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Total net sales										(319)	(314)	(278)
Total cost of sales										319	314	278
(Loss) gain related to business divestitures											0
Impairment charge											0
Operating income (loss)										0	0	0
Interest expense										0	0	0
Interest and other income, net										0	0	0
Debt retirement charge										0	0
Income (loss) from continuing operations before income taxes										0	0	0
(Provision) benefit for income taxes										0	0	0
Equity in net income of consolidated subsidiaries										(596)	362	(523)
Income from continuing operations										(596)	362	(523)
Income from discontinued operations, net of income tax										0	0	0
Net (loss) income										(596)	362	(523)
Net income attributable to noncontrolling interests										(14)	(15)	(13)
Net income (loss) attributable to L3										(610)	347	(536)
Comprehensive (loss) income attributable to L3										$ (543)	$ 462	$ (403)
[1]	See Note 3 for information regarding the Company's business divestitures.
[2]	Represents non-cash goodwill impairment charges recorded during 2015, including (i) $338 million related to a decline in the estimated fair value of the Vertex Aerospace reporting unit, and (ii) $46 million related to a business retained by L3 in connection with the sale of the NSS business, comprised of (i) $37 million related to the re-allocation of impairment charges recorded for the NSS reporting unit in 2015, and (ii) $9 million related to the re-allocation of goodwill. See Note 6 for additional information.

Financial Information of L3 120

Financial Information of L3 and Its Subsidiaries, Condensed Combining Statements of Cash Flows (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities:
Net cash from operating activities from continuing operations	$ 1,097	$ 1,069	$ 1,088
Investing activities:
Business acquisitions, net of cash acquired	(388)	(320)	(57)
Proceeds from sale of business, net of closing date cash balances	561	318	1
Other investing activities	(189)	(190)	(164)
Net cash used in investing activities from continuing operations	(16)	(192)	(221)
Financing activities:
Proceeds from sale of senior notes	547	0	996
Repurchases of senior notes	(856)	(297)	0
Redemption of CODES	0	0	(935)
Common stock repurchased	(373)	(740)	(823)
Dividends paid on L3's common stock	(220)	(214)	(208)
Other financing activities	46	46	77
Net cash used in financing activities from continuing operations	(856)	(1,205)	(893)
Effect of foreign currency exchange rate changes on cash	(13)	(19)	(17)
Net increase in cash and cash equivalents of discontinued operations	(56)	51	46
Change in cash balance in assets held for sale	0	61	(61)
Net (decrease) increase in cash	156	(235)	(58)
Cash and cash equivalents, beginning of the year	207	442	500
Cash and cash equivalents, end of the year	363	207	442
L3 [Member]
Operating activities:
Net cash from operating activities from continuing operations	482	616	467
Investing activities:
Business acquisitions, net of cash acquired	(388)	(320)	(57)
Proceeds from sale of business, net of closing date cash balances	563	14
Other investing activities	(60)	(84)	(58)
Net cash used in investing activities from continuing operations	115	(390)	(115)
Financing activities:
Proceeds from sale of senior notes	547		996
Repurchases of senior notes	(856)	(297)
Redemption of CODES			(935)
Common stock repurchased	(373)	(740)	(823)
Dividends paid on L3's common stock	(220)	(214)	(208)
Other financing activities	459	801	721
Net cash used in financing activities from continuing operations	(443)	(450)	(249)
Effect of foreign currency exchange rate changes on cash	0	0	0
Net increase in cash and cash equivalents of discontinued operations	0	0	0
Change in cash balance in assets held for sale		0	0
Net (decrease) increase in cash	154	(224)	103
Cash and cash equivalents, beginning of the year	137	361	258
Cash and cash equivalents, end of the year	291	137	361
Guarantor Subsidiaries [Member]
Operating activities:
Net cash from operating activities from continuing operations	542	422	571
Investing activities:
Business acquisitions, net of cash acquired	0	0	0
Proceeds from sale of business, net of closing date cash balances	0	28
Other investing activities	(86)	(69)	(85)
Net cash used in investing activities from continuing operations	(86)	(41)	(85)
Financing activities:
Proceeds from sale of senior notes	0		0
Repurchases of senior notes	0	0
Redemption of CODES			0
Common stock repurchased	0	0	0
Dividends paid on L3's common stock	0	0	0
Other financing activities	(399)	(434)	(530)
Net cash used in financing activities from continuing operations	(399)	(434)	(530)
Effect of foreign currency exchange rate changes on cash	0	0	0
Net increase in cash and cash equivalents of discontinued operations	(56)	51	46
Change in cash balance in assets held for sale		1	(1)
Net (decrease) increase in cash	1	(1)	1
Cash and cash equivalents, beginning of the year	0	1	0
Cash and cash equivalents, end of the year	1	0	1
Non-Guarantor Subsidiaries [Member]
Operating activities:
Net cash from operating activities from continuing operations	259	216	143
Investing activities:
Business acquisitions, net of cash acquired	0	0	0
Proceeds from sale of business, net of closing date cash balances	(2)	276
Other investing activities	(43)	(37)	(21)
Net cash used in investing activities from continuing operations	(45)	239	(21)
Financing activities:
Proceeds from sale of senior notes	0		0
Repurchases of senior notes	0	0
Redemption of CODES			0
Common stock repurchased	0	0	0
Dividends paid on L3's common stock	0	0	0
Other financing activities	(159)	(473)	(164)
Net cash used in financing activities from continuing operations	(159)	(473)	(164)
Effect of foreign currency exchange rate changes on cash	(13)	(19)	(17)
Net increase in cash and cash equivalents of discontinued operations	0	0	0
Change in cash balance in assets held for sale		60	(60)
Net (decrease) increase in cash	42	23	(119)
Cash and cash equivalents, beginning of the year	165	142	261
Cash and cash equivalents, end of the year	207	165	142
Eliminations [Member]
Operating activities:
Net cash from operating activities from continuing operations	(186)	(185)	(93)
Investing activities:
Business acquisitions, net of cash acquired	0	0	0
Proceeds from sale of business, net of closing date cash balances	0	0
Other investing activities	0	0	0
Net cash used in investing activities from continuing operations	0	0	0
Financing activities:
Proceeds from sale of senior notes	0		0
Repurchases of senior notes	0	0
Redemption of CODES			0
Common stock repurchased	0	0	0
Dividends paid on L3's common stock	0	0	0
Other financing activities	145	152	50
Net cash used in financing activities from continuing operations	145	152	50
Effect of foreign currency exchange rate changes on cash	0	0	0
Net increase in cash and cash equivalents of discontinued operations	0	0	0
Change in cash balance in assets held for sale		0	0
Net (decrease) increase in cash	(41)	(33)	(43)
Cash and cash equivalents, beginning of the year	(95)	(62)	(19)
Cash and cash equivalents, end of the year	$ (136)	$ (95)	$ (62)