Huntington Ingalls Industries (HII) 10-K 14 Feb 19 2018 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Feb. 08, 2019	Jun. 30, 2018
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2018
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2,018
Entity Registrant Name	HUNTINGTON INGALLS INDUSTRIES, INC.
Entity Central Index Key	1,501,585
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		41,529,911
Entity Well-known Seasoned Issuer	Yes
Entity Public Float			$ 9,399
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Shell Company	false

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Sales and service revenues	$ 8,176	$ 7,441	$ 7,068
Cost of sales and service revenues
Income (loss) from operating investments, net	17	12	6
Other income and gains	14		15
General and administrative expenses	871	759	768
Operating income (loss)	951	881	876
Other income (expense)
Interest expense	(58)	(94)	(74)
Non-operating retirement benefit (expense)	74	(16)	(18)
Other, net	4	1
Earnings (loss) before income taxes	971	772	784
Federal and foreign income taxes	135	293	211
Net earnings (loss)	$ 836	$ 479	$ 573
Basic earnings (loss) per share	$ 19.09	$ 10.48	$ 12.24
Weighted-average common shares outstanding (in shares)	43.8	45.7	46.8
Diluted earnings (loss) per share	$ 19.09	$ 10.46	$ 12.14
Weighted-average diluted shares outstanding (in shares)	43.8	45.8	47.2
Other comprehensive income (loss)
Change in unamortized benefit plan costs	$ (232)	$ 59	$ (172)
Other	(2)	14	(1)
Tax benefit (expense) for items of other comprehensive income	59	(22)	67
Other comprehensive income (loss), net of tax	(175)	51	(106)
Comprehensive income (loss)	661	530	467
Product [Member]
Sales and service revenues	6,023	5,573	5,631
Cost of sales and service revenues
Cost of sales and services revenues	4,627	4,277	4,237
Service [Member]
Sales and service revenues	2,153	1,868	1,437
Cost of sales and service revenues
Cost of sales and services revenues	$ 1,758	$ 1,536	$ 1,208

Consolidated Statements of Fina

Consolidated Statements of Financial Position - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Current Assets
Cash and cash equivalents	$ 240	$ 701
Accounts receivable, net	252	429
Contract assets	1,003	759
Inventoried costs, net	128	183
Prepaid expenses and other current assets	122	123
Total current assets	1,745	2,195
Land and land improvements	321	292
Buildings and leasehold improvements	2,043	1,923
Machinery and other equipment	1,771	1,559
Capitalized software costs	211	211
Property, plant and equipment, gross	4,346	3,985
Accumulated depreciation and amortization	(1,829)	(1,770)
Property, plant, and equipment, net	2,517	2,215
Other Assets
Goodwill	1,263	1,217
Other intangible assets, net	492	508
Long-term deferred tax assets	163	114
Miscellaneous other assets	203	125
Total other assets	2,121	1,964
Total assets	6,383	6,374
Current Liabilities
Trade accounts payable	562	375
Accrued employees' compensation	248	245
Current portion of postretirement plan liabilities	131	139
Current portion of workers' compensation liabilities	225	250
Contract liabilities	331	146
Other current liabilities	332	236
Total current liabilities	1,829	1,391
Long-term debt	1,283	1,279
Pension plan liabilities	764	922
Other postretirement plan liabilities	348	414
Workers' compensation liabilities	454	509
Other long-term liabilities	189	101
Total liabilities	4,867	4,616
Commitments and Contingencies (Note 16)
Stockholders' Equity
Common stock	1	1
Additional paid-in capital	1,954	1,942
Retained earnings (deficit)	2,609	1,687
Treasury stock	(1,760)	(972)
Accumulated other comprehensive income (loss)	(1,288)	(900)
Total stockholders' equity	1,516	1,758
Total liabilities and stockholders' equity	$ 6,383	$ 6,374

Consolidated Statements Of Fi_2

Consolidated Statements Of Financial Position (Parenthetical) - USD ($) shares in Millions, $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	150	150
Common stock, shares issued	53.1	53
Common stock, shares outstanding	41.9	45.1
Allowance for Doubtful Accounts Receivable, Current	$ 9	$ 13
Finite-Lived Intangible Assets, Accumulated Amortization	$ 564	$ 528

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Activities
Net earnings (loss)	$ 836	$ 479	$ 573
Adjustments to reconcile to net cash provided by (used in) operating activities
Depreciation	167	165	163
Amortization of purchased intangibles	36	40	23
Amortization of debt issuance costs	4	6	5
Provision for doubtful accounts	(4)	10
Stock-based compensation	36	34	36
Deferred income taxes	10	184	85
Loss on early extinguishment of debt		22
Change in
Accounts receivable	195	(126)	(16)
Contract assets	(242)	91	(6)
Inventoried costs	40	18	75
Prepaid expenses and other assets	(40)	(52)	(17)
Accounts payable and accruals	335	102	(41)
Retiree benefits	(454)	(163)	(44)
Other non-cash transactions, net	(5)	4	(14)
Net cash provided by (used in) operating activities	914	814	822
Capital expenditures
Capital expenditure additions	(463)	(382)	(285)
Grant proceeds for capital expenditures	61	21
Acquisitions of businesses, net of cash received	(77)	3	(372)
Investment in affiliates	(10)
Proceeds from disposition of assets	13	9	4
Net cash provided by (used in) investing activities	(476)	(349)	(653)
Financing Activities
Proceeds from issuance of long-term debt		600
Repayment of long-term debt		(600)
Proceeds from line of credit borrowings	95
Repayment of line of credit borrowings	(95)
Debt issuance costs		(12)
Premiums and fees related to early extinguishment of debt		(15)
Dividends paid	(132)	(115)	(98)
Repurchases of common stock	(742)	(286)	(194)
Employee taxes on certain share-based payment arrangements	(25)	(56)	(51)
Net cash provided by (used in) financing activities	(899)	(484)	(343)
Change in cash and cash equivalents	(461)	(19)	(174)
Cash and cash equivalents, beginning of period	701	720	894
Cash and cash equivalents, end of period	240	701	720
Supplemental Cash Flow Disclosure
Cash paid for income taxes	142	223	229
Cash paid for interest	62	72	71
Non-Cash Investing and Financing Activities
Capital expenditures accrued in accounts payable	55	33	24
Accrued repurchases of common stock	$ 48	$ 2
Capital assets received from government grants			$ 30

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings (Deficit)	Treasury Stock	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2015	$ 1,490	$ 1	$ 1,978	$ 848	$ (492)	$ (845)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	573			573
Dividends declared	(98)			(98)
Additional paid-in capital	(14)		(14)
Other comprehensive income (loss), net of tax	(106)					(106)
Treasury stock activity	(192)				(192)
Balance at Dec. 31, 2016	1,653	1	1,964	1,323	(684)	(951)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	479			479
Dividends declared	(115)			(115)
Additional paid-in capital	(22)		(22)
Other comprehensive income (loss), net of tax	51					51
Treasury stock activity	(288)				(288)
Balance at Dec. 31, 2017	1,758	1	1,942	1,687	(972)	(900)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	836			836
Dividends declared	(132)			(132)
Additional paid-in capital	12		12
Other comprehensive income (loss), net of tax	(175)					(175)
Treasury stock activity	(788)				(788)
Cumulative Effect of ASU 2014-09	5			5
Cumulative Effect of ASU 2016-01				11		(11)
Cumulative Effect of ASU 2018-02				202		(202)
Balance at Dec. 31, 2018	$ 1,516	$ 1	$ 1,954	$ 2,609	$ (1,760)	$ (1,288)

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Equity (Parenthetical) - $ / shares	3 Months Ended										12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Stockholders' Equity [Abstract]
Dividends declared per share	$ 0.86	$ 0.72	$ 0.72	$ 0.72	$ 0.72	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.50	$ 3.02	$ 2.52	$ 2.10

Description of Business

Description of Business	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	DESCRIPTION OF BUSINESS Huntington Ingalls Industries, Inc. ("HII" or the "Company") is one of America’s largest military shipbuilding companies and a provider of professional services to partners in government and industry. HII is organized into three reportable segments: Ingalls Shipbuilding ("Ingalls"), Newport News Shipbuilding ("Newport News"), and Technical Solutions. For more than a century, the Company's Ingalls segment in Mississippi and Newport News segment in Virginia have built more ships in more ship classes than any other U.S. naval shipbuilder. The Technical Solutions segment provides a range of services to the governmental, energy, and oil and gas markets. HII conducts most of its business with the U.S. Government, primarily the Department of Defense ("DoD"). As prime contractor, principal subcontractor, team member, or partner, the Company participates in many high-priority U.S. defense technology programs. Through its Ingalls segment, HII is a builder of amphibious assault and expeditionary ships for the U.S. Navy, the sole builder of National Security Cutters for the U.S. Coast Guard, and one of only two companies that builds the Navy's current fleet of Arleigh Burke class (DDG 51) destroyers. Through its Newport News segment, HII is the nation's sole designer, builder and refueler of nuclear-powered aircraft carriers, and one of only two companies currently designing and building nuclear-powered submarines for the U.S. Navy. The Technical Solutions segment provides a wide range of professional services, including fleet support, mission driven innovative solutions ("MDIS"), nuclear and environmental, and oil and gas services.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Signifcant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Principles of Consolidation - The consolidated financial statements of HII and its subsidiaries have been prepared in conformity with accounting principles generally accepted in the United States of America ("GAAP") and the instructions to Form 10-K promulgated by the Securities and Exchange Commission ("SEC"). All intercompany transactions and balances are eliminated in consolidation. For classification of current assets and liabilities related to its long-term production contracts, the Company uses the duration of these contracts as its operating cycle, which is generally longer than one year. Additionally, certain prior year amounts have been reclassified to conform to the current year presentation. See Note 3: Accounting Standards Updates. Accounting Estimates - The preparation of the Company's consolidated financial statements requires management to make estimates and judgments that affect the reported amounts of assets and liabilities and the disclosure of contingencies at the date of the financial statements, as well as the reported amounts of revenues and expenses during the reporting period. Estimates have been prepared on the basis of the most current and best available information, and actual results could differ materially from those estimates. In August 2011, the Budget Control Act established limits on U.S. Government discretionary spending, and provided for potential sequestration cuts to defense spending and non-defense discretionary spending. The Bipartisan Budget Act of 2018 (the "BBA 2018") provided sequestration relief for fiscal years 2018 and 2019. Sequestration remains in effect for fiscal years 2020 and 2021 and could result in significant decreases in DoD spending that could negatively impact the Company's consolidated financial position, results of operations, or cash flows, as well as its estimated recovery of goodwill and other long-lived assets. Revenue Recognition - Effective January 1, 2018, the Company adopted the requirements of Accounting Standards Update ("ASU") 2014-09, Revenue from Contracts with Customers (Topic 606), and related amendments . Prior to January 1, 2018, the Company recognized revenue in accordance with Accounting Standards Codification Topic 605-35 Construction-Type and Production-Type Contracts utilizing the cost-to-cost measure of the percentage-of-completion method of accounting, primarily based upon total costs incurred, with incentive fees included in sales when the amounts could be reasonably determined and estimated . Amounts representing change orders, claims, requests for equitable adjustment, or limitations of funding were included in sales only when they could be reliably estimated and realization was probable. For services contracts not associated with the design, development, manufacture, or modification of complex equipment, revenues were recognized upon delivery or as services are rendered once persuasive evidence of an arrangement exists, the price is fixed or determinable, and collectability is reasonably assured. Costs related to these contracts were expensed as incurred. For additional information on the new standard and the impact to the Company's results of operations, refer to Note 3: Accounting Standards Updates. Most of the Company's revenues are derived from long-term contracts for the production of goods and services provided to its U.S. Government customers. The Company generally recognizes revenues on contracts with U.S. Government customers over time using a cost-to-cost measure of progress. The use of the cost-to-cost method to measure performance progress over time is supported by clauses in the related contracts that allow the customer to unilaterally terminate the contract for convenience, pay the Company for costs incurred plus a reasonable profit, and take control of any work in process. The Company utilizes the cost-to-cost method to measure performance progress, because it best reflects the continuous transfer of control over the related goods and services to the customer as the Company satisfies its performance obligations. When the customer is not a U.S. Government entity, the Company may recognize revenue over time or at a point in time when control transfers upon delivery, depending upon the facts and circumstances of the related arrangement. When the Company determines that revenue should be recognized over time, the Company utilizes a measure of progress that best depicts the transfer of control of the relevant goods and services to the customer. Generally, the terms and conditions of the contracts result in a transfer of control over the related goods and services as the Company satisfies its performance obligations. Accordingly, the Company recognizes revenue over time using the cost-to-cost method to measure performance progress. The Company may, however, utilize a measure of progress other than cost-to-cost, such as a labor-based measure of progress, if the terms and conditions of the arrangement require such accounting. When using the cost-to-cost method to measure performance progress, certain contracts may include costs that are not representative of performance progress, such as large upfront purchases of uninstalled materials, unexpected waste, or inefficiencies. In these cases, the Company adjusts its measure of progress to exclude such costs, with the goal of better reflecting the transfer of control over the related goods or services to the customer and recognizing revenue only to the extent of the costs incurred that reflect the Company's performance under the contract. In addition, for time and material arrangements, the Company often utilizes the practical expedient allowing the recognition of revenue in the amount the Company invoices, which corresponds with the value provided to the customer and to which the Company is entitled to payment for performance to date. A performance obligation is a promise to transfer a distinct good or service to the customer and is the unit of account for which revenue is recognized. To determine the proper revenue recognition method, consideration is given to whether two or more contracts should be combined and accounted for as one contract and whether a single contract consists of more than one performance obligation. For contracts with multiple performance obligations, the contract transaction price is allocated to each performance obligation using an estimate of the standalone selling price based upon expected cost plus a margin at contract inception, which is generally the price disclosed in the contract. Contracts are often modified to account for changes in contract specifications and requirements. In the majority of circumstances, modifications do not result in additional performance obligations that are distinct from the existing performance obligations in the contract, and the effects of the modifications are recognized as an adjustment to revenue on a cumulative catch-up basis. Alternatively, in instances in which the performance obligations in the modifications are deemed distinct, contract modifications are accounted for prospectively. The amount of revenue recognized as the Company satisfies performance obligations associated with contracts with customers is based upon the determination of transaction price. Transaction price reflects the amount of consideration to which the Company expects to be entitled for performance under the terms and conditions of the relevant contract and may reflect fixed and variable components, including shareline incentive fees whereby the value of the contract is variable based upon the amount of costs incurred, as well as other incentive fees based upon achievement of contractual schedule commitments or other specified criteria in the contract. Shareline incentive fees are determined based upon the formula under the relevant contract using the Company’s estimated cost to complete for each period. The Company generally utilizes a most likely amount approach to estimate variable consideration. In all such instances, the estimated revenues represent those amounts for which the Company believes a significant reversal of revenue is not probable. Contract Estimates - In estimating contract costs, the Company utilizes a profit-booking rate based upon performance expectations that takes into consideration a number of assumptions and estimates regarding risks related to technical requirements, feasibility, schedule, and contract costs. Management performs periodic reviews of the contracts to evaluate the underlying risks, which may increase the profit-booking rate as the Company is able to mitigate and retire such risks. Conversely, if the Company is not able to retire these risks, cost estimates may increase, resulting in a lower profit-booking rate. The cost estimation process requires significant judgment and is based upon the professional knowledge and experience of the Company’s engineers, program managers, and financial professionals. Factors considered in estimating the work to be completed and ultimate contract recovery include the availability, productivity, and cost of labor, the nature and complexity of the work to be performed, the effect of change orders, the availability of materials, the effect of any performance delays, the availability and timing of funding from the customer, and the recoverability of any claims included in the estimates to complete. Changes in estimates of sales, costs, and profits on a performance obligation are recognized using the cumulative catch-up method of accounting, which recognizes in the current period the cumulative effect of the changes in current and prior periods. A significant change in an estimate on one or more contracts in a period could have a material effect on the Company's consolidated financial position or results of operations for that period. When estimates of total costs to be incurred exceed estimates of total revenue to be earned on a performance obligation related to a complex, construction-type contract, a provision for the entire loss on the performance obligation is recognized in the period the loss is determined. Accounts Receivable - Accounts receivable include amounts related to any unconditional Company right to receive consideration and are presented as receivables in the condensed consolidated statement of financial position, separate from other contract balances. Accounts receivable are comprised of amounts billed and currently due from customers. The Company reports accounts receivable net of an allowance for doubtful accounts. Because the Company's accounts receivable are primarily with the U.S. Government or with companies acting as a contractor to the U.S. Government, the Company does not have material exposure to accounts receivable credit risk. Contract Assets - Contract assets primarily relate to the Company’s rights to consideration for work completed but not billed as of the reporting date when the right to payment is not just subject to the passage of time, including retention amounts. Contract assets are classified as current assets and, in accordance with industry practice, include amounts that may be billed and collected beyond one year due to the long term nature of many of the Company's contracts. Contract assets are transferred to accounts receivable when the right to consideration becomes unconditional. Contract Liabilities - Contract liabilities are comprised of advance payments, billings in excess of revenues, and deferred revenue amounts. Such advances are generally not considered a significant financing component, because they are utilized to pay for contract costs within a one year period. Contract liability amounts are recognized as revenue once the requisite performance progress has occurred. Inventoried Costs - Inventoried costs primarily relate to company owned raw materials, which are stated at the lower of cost or net realizable value, generally using the average cost method, and costs capitalized pursuant to applicable provisions of the Federal Acquisition Regulation ("FAR") and U.S. Cost Accounting Standards ("CAS"). Under the Company's U.S. Government contracts, the customer asserts title to, or a security interest in, inventories related to such contracts as a result of contract advances, performance-based payments, and progress payments. In accordance with industry practice, inventoried costs are classified as current assets and include amounts related to contracts having production cycles longer than one year. Warranty Costs - Certain of the Company’s contracts contain assurance-type warranty provisions, which generally promise that the service or vessel will comply with agreed upon specifications. In such instances, the Company accrues the estimated loss by a charge to income in the relevant period. In limited circumstances, the Company's complex construction type contracts may provide the customer with an option to purchase a warranty or provide an extended assurance service coupled with the primary assurance warranty. In such cases, the Company accounts for the warranty as a separate performance obligation to the extent it is material within the context of the contract. Warranty liabilities are reported within other current liabilities and are not material. Government Grants - The Company recognizes incentive grants, inclusive of transfers of depreciable assets, from federal, state, and local governments at fair value upon compliance with the conditions of their receipt and reasonable assurance that the grants will be received or the depreciable assets will be transferred. Grants in recognition of specific expenses are recognized in the same period as an offset to those related expenses. Grants related to depreciable assets are recognized over the periods and in the proportions in which depreciation expense on those assets is recognized. For the years ended December 31, 2018 and 2017 , the Company recognized cash grant benefits of $61 million and $21 million , respectively, in other long-term liabilities in the consolidated statements of financial position. For the year ended December 31, 2016, the Company recognized grant benefits of approximately $30 million in depreciable assets and approximately $15 million in other income and gains within the consolidated statements of operations and comprehensive income, and recognized approximately $15 million in grant benefits in other long-term liabilities in the consolidated statements of financial position. General and Administrative Expenses - In accordance with industry practice and regulations that govern the cost accounting requirements for government contracts, most general corporate expenses incurred at both the segment and corporate locations are allowable and allocable costs on government contracts. These costs are allocated to contracts in progress on a systematic basis, and contract performance factors include this as an element of cost. General and administrative expenses also include certain other costs that do not affect segment operating income, primarily non-current state income taxes. Non-current state income taxes include deferred state income taxes, which reflect the change in deferred state tax assets and liabilities, and the tax expense or benefit associated with changes in state uncertain tax positions in the relevant period. Research and Development - Company-sponsored research and development activities primarily include independent research and development ("IR&D") related to experimentation, design, development, and test activities for government programs. IR&D expenses are included in general and administrative expenses and are generally allocable to government contracts. Company-sponsored IR&D expenses totaled $25 million , $17 million , and $19 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. Expenses for research and development sponsored by the customer are charged directly to the related contracts. Environmental Costs - Environmental liabilities are accrued when the Company determines remediation costs are probable and such costs are reasonably estimable. When only a range of costs is established and no amount within the range is more probable than another, the minimum amount in the range is accrued. Environmental liabilities are recorded on an undiscounted basis and are not material. Environmental expenditures are expensed or capitalized as appropriate. Capitalized expenditures, if any, relate to long-lived improvements in currently operating facilities. The Company does not record insurance recoveries before collection is probable. As of December 31, 2018 and 2017 , the Company did not have any accrued receivables related to insurance reimbursements or recoveries for environmental matters. Fair Value of Financial Instruments - The accounting standard for fair value measurements provides a framework for measuring fair value and requires expanded disclosures regarding fair value measurements. 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 on the measurement date. The accounting standard provides a fair value hierarchy, which requires an entity to maximize the use of observable inputs, where available. The three levels of inputs consist of: Level 1: Quoted prices in active markets for identical assets and liabilities. Level 2: Observable inputs, other than Level 1 prices, such as: quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or that the Company corroborates with observable market data for substantially the full term of the related assets or liabilities. Level 3: Unobservable inputs supported by little or no market activity that are significant to the fair value of the assets and liabilities. Except for the Company's long-term debt, the carrying amounts of the Company's financial instruments recorded at historical cost approximate fair value due to the short-term nature of the instruments and low credit risk associated with the respective counterparties. The Company maintains multiple grantor trusts to fund certain non-qualified pension plans. These trusts were valued at $109 million and $94 million as of December 31, 2018 and 2017 , respectively, and are presented within miscellaneous other assets within the consolidated statements of financial position. These trusts consist primarily of investments in marketable securities, which are held at fair value within Level 1 of the fair value hierarchy. Foreign Currency Translation - The Company's international subsidiaries that do not have the U.S. dollar as their functional currency translate assets and liabilities at current rates of exchange in effect at the balance sheet date. Revenues and expenses from these international subsidiaries are translated using the monthly average exchange rates in effect for the periods in which the items occur. The cumulative foreign currency translation gains and losses are included as a component of accumulated other comprehensive loss in stockholders’ equity. Gains and losses from foreign currency transactions are included in other income (expense) in the consolidated statements of operations and comprehensive income. Such amounts are not material. Asset Retirement Obligations - Environmental remediation and/or asset decommissioning may be required when the Company ceases to utilize certain facilities. The Company records, within other current liabilities or other long-term liabilities as appropriate, all known asset retirement obligations for which the liability's fair value can be reasonably estimated, including certain asbestos removal, asset decommissioning, and lease restoration obligations. Asset retirement obligations for which the liability's fair value can be reasonably estimated were immaterial as of December 31, 2018 and 2017 . The Company also has known conditional asset retirement obligations related to assets currently in use, including certain asbestos remediation and asset decommissioning activities to be performed in the future, that were not reasonably estimable as of December 31, 2018 , due to insufficient information about the timing and method of settlement of the obligation. Accordingly, the fair value of these obligations has not been recorded in the consolidated financial statements. A liability for these obligations is recorded in the period in which sufficient information regarding timing and method of settlement becomes available to make a reasonable estimate of the liability's fair value. In addition, there may be conditional environmental asset retirement obligations that the Company has not yet discovered. Income Taxes - Income tax expense and other related information are based on the prevailing statutory rates for U.S. federal income taxes and the composite state income tax rate for the Company for each period presented. Non-current state income taxes include deferred state income taxes, which reflect the change in deferred state tax assets and liabilities, and the tax expense or benefit associated with changes in state uncertain tax positions in the relevant period. These amounts are recorded within operating income, while the current period state income tax expense, which is generally allowable and allocable to contracts, is charged to contract costs and included in cost of sales and service revenues in segment operating income. Deferred income taxes are recorded when revenues and expenses are recognized in different periods for financial statement purposes and for tax return purposes. Deferred tax asset or liability account balances are calculated at the balance sheet date using current tax laws and rates expected to be in effect when the deferred tax items reverse in future periods. As a result of the reduction in the corporate income tax rate from 35% to 21% effective January 1, 2018, under the Tax Cuts and Jobs Act (the "Tax Act"), the Company revalued its net deferred tax assets. See Note 13: Income Taxes in Item 8. The Company recognizes deferred tax assets to the extent it believes these assets are more likely than not to be realized. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. Based on the Company's evaluation of these deferred tax assets, valuation allowances of $12 million were deemed necessary as of each of December 31, 2018 and 2017 . Uncertain tax positions meeting the more-likely-than-not recognition threshold, based on the merits of the position, are recognized in the financial statements. The Company recognizes the amount of tax benefit that is greater than 50% likely to be realized upon ultimate settlement with the related tax authority. If a tax position does not meet the minimum statutory threshold to avoid payment of penalties, the Company recognizes an expense for the amount of the penalty in the period the tax position is claimed or expected to be claimed in its tax return. Penalties and accrued interest related to uncertain tax positions are recognized as a component of income tax expense. Changes in accruals associated with uncertain tax positions are recorded in earnings in the period in which they are determined. Cash and Cash Equivalents - The carrying amounts of cash and cash equivalents approximate fair value due to the short-term nature of these assets, which have original maturity dates of 90 days or less. Concentration Risk - The Company’s assets that are exposed to concentrations of credit risk consist primarily of cash and cash equivalents. The Company places its cash and cash equivalents with reputable financial institutions and limits the amount of credit exposure with any one of them. The Company regularly evaluates the creditworthiness of these financial institutions and minimizes this credit risk by entering into transactions with high-quality counterparties, limiting the exposure to each counterparty, and monitoring the financial condition of its counterparties. In connection with its U.S. Government contracts, the Company is required to procure certain raw materials, components, and parts from supply sources approved by the U.S. Government. Only one supplier may exist for certain components and parts required to manufacture the Company's products. Property, Plant, and Equipment - Depreciable properties owned by the Company are recorded at cost and depreciated over the estimated useful lives of individual assets. Major improvements are capitalized while expenditures for maintenance, repairs, and minor improvements are expensed. Costs incurred for computer software developed or purchased for internal use are capitalized and amortized over the expected useful life of the software, not to exceed nine years. Leasehold improvements are amortized over the shorter of their useful lives or the term of the lease. The remaining assets are depreciated using the straight-line method, with the following lives: Years Land improvements 2 - 40 Buildings and improvements 2 - 60 Capitalized software costs 3 - 9 Machinery and other equipment 2 - 45 The Company evaluates the recoverability of its property, plant, and equipment when there are changes in economic circumstances or business objectives that indicate the carrying value may not be recoverable. The Company's evaluations include estimated future cash flows, profitability, and other factors affecting fair value. As these assumptions and estimates may change over time, it may or may not be necessary to record impairment charges. Leases - The Company uses its incremental borrowing rate in the assessment of lease classification as capital or operating and defines the initial lease term to include renewal options determined to be reasonably assured. The Company conducts operations primarily under operating leases. Many of the Company's real property lease agreements contain incentives for tenant improvements, rent holidays, or rent escalation clauses. For incentives for tenant improvements, the Company records a deferred rent liability and amortizes the deferred rent over the term of the lease as a reduction to rent expense. For rent holidays and rent escalation clauses during the lease term, the Company records minimum rental expenses on a straight-line basis over the term of the lease. For purposes of recognizing lease incentives, the Company uses the date of initial possession as the commencement date, which is generally the date on which the Company is given the right of access to the space and begins to make improvements in preparation for the intended use. Goodwill and Other Intangible Assets - The Company performs impairment tests for goodwill as of November 30 of each year and between annual impairment tests if evidence of potential impairment exists, by comparing the carrying value of net assets to the fair value of the reporting unit. If the fair value is determined to be less than the carrying value, the Company records an impairment charge to the reporting unit. Purchased intangible assets are amortized on a straight-line basis or a method based on the pattern of benefits over their estimated useful lives, and the carrying value of these assets is reviewed for impairment when events indicate that a potential impairment may have occurred. Equity Method Investments - Investments in which the Company has the ability to exercise significant influence over the investee but does not own a majority interest or otherwise control are accounted for under the equity method of accounting and included in other assets in its consolidated statements of financial position. The Company's equity investments align strategically and are integrated with the Company's operations. Accordingly, the Company's share of the net earnings or losses of the investee is included in operating income. The Company evaluates its equity investments for other than temporary impairment whenever events or changes in business circumstances indicate that the carrying amounts of such investments may not be fully recoverable. If a decline in the value of an equity method investment is determined to be other than temporary, a loss is recorded in earnings in the current period. Self-Insured Group Medical Insurance - The Company maintains a self-insured group medical insurance plan. The plan is designed to provide a specified level of coverage for employees and their dependents. Estimated liabilities for incurred but not paid claims utilize actuarial methods based on various assumptions, which include, but are not limited to, HII's historical loss experience and projected loss development factors. These liabilities are recorded in other current liabilities and account for less than 5% of the total current liabilities balance. Self-Insured Workers' Compensation Plan - The operations of the Company are subject to federal and state workers' compensation laws. The Company maintains self-insured workers' compensation plans and participates in federally administered second injury workers' compensation funds. The Company estimates the liability for claims and funding requirements on a discounted basis utilizing actuarial methods based on various assumptions, which include, but are not limited to, the Company's historical loss experience and projected loss development factors as compiled in an annual actuarial study. Self-insurance accruals include amounts related to the liability for reported claims and an estimated accrual for claims incurred but not reported. The Company's workers' compensation liability was discounted at 2.89% and 2.35% as of December 31, 2018 and 2017 , respectively. These discount rates were determined using a risk-free rate based on future payment streams. Workers' compensation benefit obligations on an undiscounted basis were $845 million and $925 million as of December 31, 2018 and 2017 , respectively. Litigation, Commitments, and Contingencies - Amounts associated with litigation, commitments, and contingencies are recorded as charges to earnings when management, after taking into consideration the facts and circumstances of each matter, including any settlement offers and projected loss or claim development factors, has determined it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Restructuring - Restructuring related accruals are reviewed and adjusted when circumstances require such a change. Accruals for restructuring activities include estimates primarily related to facility consolidations and closures, asset retirement obligations, long-lived asset write-downs, employment reductions, and contract termination costs. There are no restructuring accruals or activity as of and for the years ended December 31, 2018 , 2017 and 2016 . Loan Receivable - The Company holds a loan receivable in connection with a seller financed transaction involving its previously owned Avondale Shipyard facility. The receivable is carried at amortized cost in the amount of $38 million , net of a $10 million loan discount, which approximates fair value and is recorded in miscellaneous other assets on the consolidated statements of financial position. Interest income is recognized on an accrual basis using the effective yield method. The discount is accreted into income using the effective yield method over the estimated life of the loan receivable. Retirement Related Benefit Costs - The Company accounts for its retirement related benefit plans on the accrual basis. The measurements of obligations, costs, assets, and liabilities require significant judgment. The costs of benefits provided by defined benefit pension plans are recorded in the period participating employees provide service. The costs of benefits provided by other postretirement benefit plans are recorded in the period participating employees attain full eligibility. The discount rate assumption is defined under GAAP as the rate at which a plan's obligation could be effectively settled. The discount rate is established for each of the retirement related benefit plans at its respective measurement date. The expected return on plan assets component of retirement related costs is used to calculate net periodic expense. Unless plan assets and benefit obligations are subject to remeasurement during the year, the expected return on assets is based on the fair va

Accounting Standards Updates

Accounting Standards Updates	12 Months Ended
	Dec. 31, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Accounting Standards Updates	ACCOUNTING STANDARDS UPDATES Effective January 1, 2018, the Company adopted the requirements of ASU 2014-09, "Revenue from Contracts with Customers (Topic 606), " and related amendments, which provide a single revenue recognition model under which the Company should recognize revenue to portray the transfer of promised goods or services in a manner reflective of the consideration the Company is entitled to receive in exchange for those goods or services. The Company used the modified retrospective method and related practical expedient in its application of the new standard to those contracts that were not completed as of January 1, 2018, and reflected the cumulative effect of changes in the opening balance of retained earnings. Results for reporting periods beginning after January 1, 2018, were presented under Topic 606, while prior period amounts were not adjusted and were reported in accordance with the Company's historic accounting practices under Topic 605. The adoption of Topic 606 did not have a significant impact on the Company's condensed consolidated financial statements, contracting and accounting processes, internal controls, or information technology systems. For the consolidated statements of operations and comprehensive income, the new standard supports the recognition of revenue over time under the cost-to-cost input method, which is consistent with the Company’s previous revenue recognition model for a substantial majority of its contracts. The most significant impact of the new standard was the modification and expansion of the Company’s disclosures as they relate to revenues and contract balances. Pre-contract fulfillment costs requiring capitalization are not material. On the Company’s consolidated statements of financial position, contract assets and liabilities are reported in a net position on a contract-by-contract basis at the end of each reporting period. The application of the new standard is materially consistent with the Company’s previous accounting policies related to contract balances. In accordance with the new standard, unbilled accounts receivable were reclassified as contract assets and advance payments and billings in excess of revenue were reclassified as contract liabilities as of December 31, 2018 and 2017 , none of which resulted in a change to total current assets or total current liabilities. As part of the transition, the Company also classified in contract assets approximately $64 million of retention amounts arising from contractual provisions, since the right to collect is based on certain conditions other than the passage of time. These retention amounts were previously reported within billed accounts receivable. Under Topic 605, the Company included warranty costs specified in a contract as contract costs. Under Topic 606, assurance-type warranty costs are not deemed to be part of a performance obligation and, therefore, are included within warranty liabilities, which are not material. The adoption of Topic 606 resulted in a cumulative increase to retained earnings of $5 million , net of $1 million tax expense, as of January 1, 2018, driven by changes in contract assets and warranty liabilities. For the year ended December 31, 2018 , each of product sales, operating income, and net earnings increased by less than $1 million and diluted earnings per share increased by $0.01 , due to the adoption of Topic 606. In January 2016, the FASB issued ASU 2016‑01, "Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities," relating to the recognition and measurement of financial assets and liabilities, with further clarifications made in February 2018 with the issuance of ASU 2018-03. The amended guidance requires certain equity investments that are not consolidated and not accounted for under the equity method to be measured at fair value, with changes in fair value recognized in net income rather than as a component of accumulated other comprehensive loss. The Company adopted this amended guidance on January 1, 2018, using a modified retrospective transition approach, which did not have a significant impact on the Company's condensed consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, "Leases (Topic 842)," which establishes a right-of-use model that requires a lessee to record the right-of-use asset and a lease liability on the balance sheet for all leases with terms longer than 12 months. Additional qualitative and quantitative disclosures are required. Prior to the FASB issuing ASU 2018-11 “Leases”, entities were required to use a modified retrospective approach upon adoption to recognize and measure leases at the beginning of the earliest comparative period presented in the financial statements. In July 2018, the FASB issued ASU 2018-11, which provides entities the option to initially apply ASU 2016-02 at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption. Consequently, the comparative periods presented in the financial statements would continue to comply with current GAAP. The Company has completed its assessment of leasing arrangements and service contracts and the related impacts to its business processes, internal controls, and financial statements. The Company adopted the new standard effective January 1, 2019, using the optional transition method permitted by ASU 2018-11. The Company elected the package of practical expedients permitted under the transition guidance within the new standard, which, among other things, allows it to carry forward historical lease classifications. The Company also elected the hindsight practical expedient to determine the reasonably certain lease term for existing leases. The Company's election of the hindsight practical expedient resulted in lengthening lease terms for certain existing leases. The Company also made an accounting policy election not to record a right-of-use asset or lease liability related to leases with an initial term of 12 months or less. The Company recognizes those lease payments in the consolidated statements of operations and comprehensive income on a straight-line basis over the lease term. The estimated impact upon adoption was an increase to right-of-use assets and lease liabilities of between $200 million and $220 million with no material impact to the opening balance of retained earnings. In January 2018, the FASB issued ASU 2018-01 Leases, “Land Easement Practical Expedient,” which permits entities to forgo the evaluation of existing land easement arrangements to determine if they contain a lease as part of the adoption of ASU 2016-02 issued in February 2016. Accordingly, the Company’s accounting treatment of any existing land easement arrangements did not change. The Company adopted this standard update concurrently with ASU 2016-02. In March 2017, the FASB issued ASU 2017-07, "Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost." The update requires employers to present the service cost component of the net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. The other components of net benefit cost, including interest cost, expected return on plan assets, amortization of prior service cost/credit and actuarial gain/loss, and settlement and curtailment effects, are presented outside of any subtotal of operating income. Employers are required to disclose the line(s) used to present the other components of net periodic benefit cost, if the components are not presented separately in the income statement. ASU 2017-07 became effective for fiscal years and interim periods beginning after December 15, 2017. The Company adopted ASU 2017-07 on January 1, 2018, using the retrospective method, which changed the FAS/CAS Adjustment within operating income, offset by a corresponding change in other income (expense), as a result of reclassifying interest cost, expected return on plan assets, amortization of prior service cost/credit and actuarial gain/loss, and settlement and curtailment effects of net periodic benefit expense. Additionally, the remaining FAS/CAS Adjustment within operating income was reclassified from general and administrative expenses to cost of product sales and service revenues. The adoption of ASU 2017-07 did not have a material impact on the Company's condensed consolidated statements of financial position, cash flows, accounting processes, or internal controls. The following table is a schedule of the impact of adoption of ASU 2017-07 for the years ended December 31, 2017 and 2016. The Company has reclassified the following line items on its previously issued consolidated financial statements to conform to the current year presentation. As Previously Reported As Revised Year Ended December 31 Year Ended December 31 ($ in millions) 2017 2016 2017 2016 Sales and service revenues Product sales $ 5,573 $ 5,631 $ 5,573 $ 5,631 Service revenues 1,868 1,437 1,868 1,437 Sales and service revenues 7,441 7,068 7,441 7,068 Cost of sales and service revenues Cost of product sales 4,444 4,380 4,277 4,237 Cost of service revenues 1,574 1,228 1,536 1,208 Income from operating investments, net 12 6 12 6 Other income and gains — 15 — 15 General and administrative expenses 570 623 759 768 Goodwill impairment — — — — Operating income 865 858 881 876 Other income (expense) Interest expense (94 ) (74 ) (94 ) (74 ) Non-operating retirement expense — — (16 ) (18 ) Other, net 1 — 1 — Earnings before income taxes 772 784 772 784 Federal and foreign income taxes 293 211 293 211 Net earnings $ 479 $ 573 $ 479 $ 573 In February 2018, the FASB issued ASU 2018-02, "Income Statement-Reporting Comprehensive Income (Topic 220), Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income," which provides for the reclassification from accumulated other comprehensive loss to retained earnings of stranded tax effects resulting from the Tax Cuts and Jobs Act (the "Tax Act"). This update was effective for all entities for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years, and early adoption was permitted. Effective January 1, 2018, the Company early adopted the amendments in this update and, accordingly, reclassified the income tax effects of the Tax Act from accumulated other comprehensive loss to retained earnings. See Note 13: Income Taxes, for further disclosure. In June 2018, the FASB issued ASU 2018-08, “Not-For-Profit Entities (Topic 958): Clarifying the Scope and the Accounting Guidance for Contributions Received and Contributions Made,” which assists entities in evaluating the nature and accounting treatment of contributions received. The update applies to all entities that receive contributions of cash or other assets, but does not apply to transfers of assets from government entities to business entities. This standard is effective for annual reporting periods beginning after December 15, 2018. The update should be applied on a modified prospective basis. The Company is currently evaluating the impact of ASU 2018-08 on its consolidated financial statements and disclosures, accounting processes, or internal controls related to periodic government grants received as reimbursements of costs or related to depreciable assets. In August 2018, the FASB issued ASU 2018-13, "Changes to the Disclosure Requirements for Fair Value Measurement," which changes the fair value measurement disclosure requirements of ASC 820. The update includes changes to disclosures regarding valuation techniques and inputs, uncertainty, judgments, and assumptions in fair value measurements, and how changes in fair value measurements affect performance and cash flows. The update is effective for annual reporting periods beginning after December 15, 2019, including interim periods therein. Early adoption is permitted for any eliminated or modified disclosures. The Company is currently evaluating the impact of ASU 2018-13 on its consolidated financial statements and disclosures, accounting processes, and internal controls. In August 2018, the FASB issued ASU 2018-14, “Changes to the Disclosure Requirements for Defined Benefit Plans,” which reduces disclosure requirements of Subtopic 715-20 and requires additional disclosure related to weighted-average interest crediting rates and significant gains and losses related to changes in the benefit obligation for the reporting period. The update is effective on a retrospective basis for fiscal years ending after December 15, 2020, with early adoption allowed. The Company is currently evaluating the impact of ASU 2018-14 on its consolidated financial statements and disclosures, accounting processes, and internal controls. In August 2018, the SEC issued a final rule that amends certain disclosure requirements it considers redundant, outdated, or superseded, including disclosures related to ratio of fixed charges, changes in stockholders' equity, dividends, and market price information. The final rule became effective in November 2018. The final rule did not have a significant impact on the Company's consolidated financial statements and disclosures, accounting processes, and internal controls. Other accounting pronouncements issued but not effective until after December 31, 2018, are not expected to have a material impact on the Company's consolidated financial position, results of operations, or cash flows.

Avondale and Gulfport

Avondale and Gulfport	12 Months Ended
	Dec. 31, 2018
Restructuring and Related Activities [Abstract]
Avondale and Gulfport	AVONDALE AND GULFPORT In October 2014, the Company ceased shipbuilding construction operations at its Avondale, Louisiana facility. In connection with winding down shipbuilding at this facility, the Company incurred and paid related restructuring and shutdown costs. Pursuant to applicable provisions of the FAR and CAS for the treatment of restructuring and shutdown related costs, the Company began amortizing the deferred costs over a five year period in 2014. In November 2017, the U.S. Government and the Company reached a settlement to treat $251 million of these costs as allowable costs, a majority of which were billed to the U.S. Government and collected by the end of 2018. The settlement was consistent with management’s cost recovery expectations and did not have a material effect on the Company’s statements of financial position or results of operations. In October 2018, the Company completed a sale of the Avondale facility. In addition to cash proceeds, the Company financed a portion of the transaction over a nine year period, resulting in a net gain of $7 million , recognized as a reduction to cost of sales in the fourth quarter of 2018. In August 2014, the Company completed closure of its Gulfport Composite Center of Excellence in Gulfport, Mississippi. In connection with this closure, the Company incurred restructuring related costs of $54 million , including $52 million of accelerated depreciation of fixed assets. In March 2015, the Company sold the Gulfport Composite Center of Excellence to the Mississippi State Port Authority, resulting in a gain on disposition of $9 million , recorded as a reduction to contract costs in accordance with the terms of the Company’s contracts with the U.S. Government. The Company reached a resolution with the U.S. Government in December 2018 regarding the treatment and allocation of the restructuring related costs, which is substantially in accordance with management's cost recovery expectations and does not have a material effect on the Company's consolidated financial position, results of operations, or cash flows.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	ACQUISITIONS On December 3, 2018, the Company acquired G2, Inc. ("G2"), a provider of cybersecurity solutions to the U.S. Government, for approximately $77 million in cash, net of $2 million of acquired cash. The acquisition was consistent with the Company's strategy to optimize and expand its services portfolio. In connection with this acquisition, the Company recorded $46 million of goodwill, which includes the value of G2's workforce, all of which was allocated to its Technical Solutions segment, as well as $20 million of intangible assets related to existing contract backlog. See Note 12: Goodwill and Other Intangible Assets. The Company has not completed the purchase price allocation due to the recent acquisition date and potential adjustments upon finalization of the net working capital adjustment and the fair values of the assets acquired and liabilities assumed. The assets, liabilities, and results of operations of G2 are not material to the Company’s consolidated financial position, results of operations, or cash flows. On December 1, 2016, the Company acquired Camber Holding Corporation ("Camber"), a provider of mission-based and information technology solutions to the U.S. Government, for approximately $369 million in cash, net of $27 million of cash acquired. The acquisition was consistent with the Company's strategy to optimize and expand its services portfolio. For the years ended December 31, 2018 and 2017, Camber contributed revenues of $315 million and $309 million , respectively, and operating income of $12 million and $8 million , respectively. In connection with this acquisition, the Company recorded $261 million of goodwill, all of which was allocated to its Technical Solutions segment, primarily related to the value of Camber's workforce, and $76 million of intangible assets related to existing contract backlog. See Note 12: Goodwill and Other Intangible Assets. For the year ended December 31, 2017, the Company recorded a goodwill adjustment of $17 million , primarily driven by the finalization of fair value calculations for certain assets and liabilities, as well as the net working capital adjustment. The assets, liabilities, and results of operations of Camber are not material to the Company’s consolidated financial position, results of operations, or cash flows. The Company funded each of these acquisitions using cash on hand. The acquisition costs incurred in connection with these acquisitions were not material. The operating results of these businesses have been included in the Company’s consolidated results as of the respective closing dates of the acquisitions. In allocating the purchase prices of these businesses, the Company considered the estimated fair value of net tangible and intangible assets acquired, with any excess purchase price recorded as goodwill. The total amount of goodwill resulting from acquisitions expected to be deductible for tax purposes was $201 million . These acquisitions are not material either individually or in the aggregate, and pro forma revenues and results of operations have therefore not been provided.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2018
Stockholders' Equity Note [Abstract]
Stockholders' Equity	STOCKHOLDERS' EQUITY Common Stock - Changes in the Company's number of outstanding shares for the year ended December 31, 2018 , resulted from shares purchased in the open market under the Company's stock repurchase program and share activity under its stock compensation plans. See Note 18: Stock Compensation Plans. Treasury Stock - In November 2017, the Company's board of directors authorized an increase in the Company's stock repurchase program from $1.2 billion to $2.2 billion and an extension of the term of the program from October 31, 2019, to October 31, 2022. Repurchases are made from time to time at management's discretion in accordance with applicable federal securities laws. For the year ended December 31, 2018 , the Company repurchased 3,620,916 shares at an aggregate cost of $788 million , of which $48 million was not yet settled for cash as of December 31, 2018 . For the years ended December 31, 2017 and 2016 , the Company repurchased 1,417,808 and 1,266,192 shares, respectively, at aggregate costs of $288 million and $192 million , respectively, of which $2 million for the year ended December 31, 2017 , was not yet settled for cash as of December 31, 2017. The cost of purchased shares is recorded as treasury stock in the consolidated statements of financial position. Dividends - In November 2018, the Company's board of directors authorized an increase in the Company's quarterly cash dividend from $0.72 per share to $0.86 per share. In November 2017, the Company's board of directors authorized an increase in the Company's quarterly cash dividend from $0.60 per share to $0.72 per share. In November 2016, the Company's board of directors authorized an increase in the Company's quarterly cash dividend from $0.50 per share to $0.60 per share. The Company paid cash dividends totaling $132 million ( $3.02 per share), $115 million ( $2.52 per share), and $98 million ( $2.10 per share) in the years ended December 31, 2018 , 2017 , and 2016 , respectively. Accumulated Other Comprehensive Loss - Other comprehensive income (loss) refers to gains and losses recorded as an element of stockholders' equity but excluded from net earnings. The accumulated other comprehensive loss as of December 31, 2018 and 2017 , was comprised of unamortized benefit plan costs of $1,283 million and $906 million , respectively, and other comprehensive income (loss) items of $(5) million and $6 million , respectively. The changes in accumulated other comprehensive loss by component for the years ended December 31, 2018 , 2017 , and 2016 , were as follows: ($ in millions) Benefit Plans Other Total Balance as of December 31, 2015 $ (843 ) $ (2 ) $ (845 ) Other comprehensive loss before reclassifications (249 ) (1 ) (250 ) Amounts reclassified from accumulated other comprehensive loss Amortization of prior service (credit) 1 (1 ) — (1 ) Amortization of net actuarial loss 1 78 — 78 Tax benefit for items of other comprehensive income 67 — 67 Net current period other comprehensive loss (105 ) (1 ) (106 ) Balance as of December 31, 2016 (948 ) (3 ) (951 ) Other comprehensive income (loss) before reclassifications (34 ) 14 (20 ) Amounts reclassified from accumulated other comprehensive loss Amortization of net actuarial loss 1 93 — 93 Tax expense for items of other comprehensive income (17 ) (5 ) (22 ) Net current period other comprehensive income 42 9 51 Balance as of December 31, 2017 (906 ) 6 (900 ) Other comprehensive loss before reclassifications (312 ) (2 ) (314 ) Amounts reclassified from accumulated other comprehensive loss Amortization of prior service cost 1 2 — 2 Amortization of net actuarial loss 1 78 — 78 Tax expense for items of other comprehensive income 59 — 59 Net current period other comprehensive loss (173 ) (2 ) (175 ) Effect of Accounting Standards Update 2016-01 2 $ — $ (11 ) $ (11 ) Effect of Accounting Standards Update 2018-02 3 $ (204 ) $ 2 $ (202 ) Balance as of December 31, 2018 $ (1,283 ) $ (5 ) $ (1,288 ) 1 These accumulated comprehensive loss components are included in the computation of net periodic benefit cost. See Note 17: Employee Pension and Other Postretirement Benefits. The tax expense associated with amounts reclassified from accumulated other comprehensive loss for the years ended December 31, 2018 , 2017 , and 2016 , was $21 million , $36 million , and $27 million , respectively. 2 The Company adopted ASU 2016-01 as of January 1, 2018. Accordingly, accumulated other comprehensive income of $11 million related to available-for-sale securities, net of $4 million tax expense, was reclassified to retained earnings. 3 The Company adopted ASU 2018-02 as of January 1, 2018. Accordingly, stranded tax effects of $202 million related to the Tax Act were reclassified to retained earnings.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE Basic and diluted earnings per common share were calculated as follows: Year Ended December 31 (in millions, except per share amounts) 2018 2017 2016 Net earnings $ 836 $ 479 $ 573 Weighted-average common shares outstanding 43.8 45.7 46.8 Net effect of dilutive stock options and awards — 0.1 0.4 Dilutive weighted-average common shares outstanding 43.8 45.8 47.2 Earnings per share - basic $ 19.09 $ 10.48 $ 12.24 Earnings per share - diluted $ 19.09 $ 10.46 $ 12.14 The Company's calculation of diluted earnings per common share includes the dilutive effects of the assumed exercise of stock options and vesting of restricted stock based on the treasury stock method. Under the treasury stock method, the Company has excluded from the diluted share amounts presented above the effects of 0.3 million Restricted Performance Stock Rights ("RPSRs") for each of the years ended December 31, 2018 and 2017. The amounts presented above for the year ended December 31, 2016 , exclude the impact of 0.1 million stock options and 0.3 million RPSRs under the treasury stock method.

Revenue

Revenue	12 Months Ended
	Dec. 31, 2018
Disaggregation of Revenue [Abstract]
Revenue Recognition, Deferred Revenue Disclosure [Text Block]	REVENUE The following is a description of principal activities from which the Company generates its revenues. For more detailed information regarding reportable segments, see Note 9: Segment Information. For more detailed information regarding the Company's significant accounting policy for revenue, see Note 2: Basis of Presentation. U.S. Government Contracts The Ingalls and Newport News segments generate revenue primarily from performance under multi-year contracts with the U.S. Government, generally the U.S. Navy and U.S. Coast Guard, or prime contractors to contracts with the U.S. Government, relating to the advance planning, design, construction, repair, maintenance, refueling, overhaul, or inactivation of nuclear-powered ships and non-nuclear ships. The period over which the Company performs may extend past five years. The Technical Solutions segment also generates the majority of its revenue from contracts with the U.S. Government, including U.S. Government agencies. The Company generally invoices and receives related payments based upon performance progress no less frequently than monthly. Shipbuilding - For most of the Company's shipbuilding contracts, the customer contracts with the Company to provide a comprehensive service of designing, procuring long-lead-time materials, manufacturing, and integrating complex equipment and technologies into a single ship or project, often resulting in a single performance obligation. Contract modifications to account for changes in specifications and requirements are recognized when approved by the customer. In the majority of circumstances, modifications do not result in additional performance obligations that are distinct from the existing performance obligations in the contract and the effects of the modifications are recognized as an adjustment to revenue on a cumulative catch-up basis. Alternatively, in instances where the performance obligations in the modifications are deemed distinct, contract modifications are accounted for prospectively. The Company considers incentive and award fees to be variable consideration and includes in the transaction price at inception the consideration to which the Company expects to be entitled under the terms and conditions of the contract, generally estimated using a most likely amount approach. Transaction price is limited to the extent of funding allotted by the customer and available for performance, and estimated revenues represent those amounts for which the Company believes a significant reversal of revenue is not probable. The Company recognizes revenues related to shipbuilding contracts as it satisfies the related performance obligations over time using a cost-to-cost input method to measure performance progress, which best reflects the transfer of control to the customer. Services - The Technical Solutions segment generates revenue primarily under U.S. Government contracts from the provision of fleet support and MDIS services. Contracts generally are structured using either an Indefinite Delivery/Indefinite Quantity ("IDIQ") vehicle, under which orders are issued, or a standalone contract. Contracts may be fixed-price or cost-type, include variable consideration such as incentives and awards, and structured as task orders under an IDIQ contract vehicle or requirements contract vehicle. In either case, the Company generally performs over the course of a short-duration period and may continue to perform upon exercise of related period of performance options that are also short in duration, generally one year. The Company’s performance obligations vary in nature and may be stand-ready, in which case the Company responds to the customer’s needs on the basis of its demand, a recurring service, in the case of recurring maintenance services, or a single performance obligation that does not comprise a series of distinct services. In determining transaction price, the Company considers incentives and other contingencies to be variable consideration and includes in the initial transaction price the consideration to which the Company expects to be entitled under the terms and conditions of the contract, generally estimated using a most likely amount approach. Transaction price is limited to the extent of funding allotted by the customer and available for performance, and estimated revenues represent those amounts for which the Company believes a significant reversal of revenue is not probable. Where a series of distinct services has been identified, the Company generally allocates variable consideration to distinct time increments of service. The Company generally recognizes revenue as it satisfies the related performance obligations over time using a cost-to-cost input method to measure performance progress, because, even where the Company has identified a series of services, its cost incurrence pattern generally is not ratable given the complex nature of the services the Company provides. Invoices are issued and related payments are received, on the basis of performance progress, no less frequently than monthly. In addition, many of the Company's U.S. Government services contracts are time and material arrangements. As a result, the Company often utilizes the practical expedient allowing the recognition of revenue in the amount the Company invoices, which corresponds with the value provided to the customer and to which the Company is entitled to payment for performance to date. Non-U.S. Government Contracts Revenues generated under commercial and state and local government agency contracts are primarily derived from the provision of nuclear and environmental and oil and gas services. Non-U.S. Government contracts typically are one or two years in duration. In determining transaction price, the Company considers incentives and other contingencies to be variable consideration and includes in the initial transaction price the consideration to which the Company expects to be entitled under the terms and conditions of the contract, generally estimated using a most likely amount approach. In the context of variable consideration, the Company limits the transaction price to amounts for which the Company believes a significant reversal of revenue is not probable. Such amounts may relate to transaction price in excess of funding, a lack of history with the customer, a lack of history with the goods or services being provided, or other items. Revenue generally is recognized over time given the terms and conditions of the related contracts. The Company generally utilizes a cost-to-cost input method to measure performance progress, which best depicts the transfer of control to the customer. The Company’s non-U.S. Government contract portfolio is comprised of a large number of time and material arrangements. As a result, the Company often utilizes the practical expedient allowing the recognition of revenue in the amount the Company invoices, which corresponds with the value provided to the customer and to which the Company is entitled to payment for performance to date. Disaggregation of Revenue The following tables present revenues on a disaggregated basis, in a manner that reconciles with the Company's reportable segment disclosures, for the following categories: product versus service type, customer type, contract type, and major program. See Note 9: Segment Information. The Company believes that this level of disaggregation provides investors with information to evaluate the Company’s financial performance and provides the Company with information to make capital allocation decisions in the most appropriate manner. Year Ended December 31, 2018 ($ in millions) Ingalls Newport News Technical Solutions Intersegment Eliminations Total Revenue Type Product sales $ 2,390 $ 3,559 $ 74 $ — $ 6,023 Service revenues 215 1,156 782 — 2,153 Intersegment 2 7 132 (141 ) — Sales and service revenues $ 2,607 $ 4,722 $ 988 $ (141 ) $ 8,176 Customer Type Federal $ 2,605 $ 4,714 $ 589 $ — $ 7,908 Commercial — 1 265 — 266 State and local government agencies — — 2 — 2 Intersegment 2 7 132 (141 ) — Sales and service revenues $ 2,607 $ 4,722 $ 988 $ (141 ) $ 8,176 Contract Type Firm fixed-price $ 81 $ 8 $ 147 $ — $ 236 Fixed-price incentive 2,167 1,876 1 — 4,044 Cost-type 357 2,831 370 — 3,558 Time and materials — — 338 — 338 Intersegment 2 7 132 (141 ) — Sales and service revenues $ 2,607 $ 4,722 $ 988 $ (141 ) $ 8,176 Year Ended December 31 ($ in millions) 2018 Major Programs Amphibious assault ships $ 1,348 Surface combatants and coast guard cutters 1,253 Other 6 Total Ingalls 2,607 Aircraft carriers 2,605 Submarines 1,476 Other 641 Total Newport News 4,722 Government and energy services 799 Oil and gas services 189 Total Technical Solutions 988 Intersegment eliminations (141 ) Sales and service revenues $ 8,176 As of December 31, 2018 , the Company had $23.0 billion of remaining performance obligations. The Company expects to recognize approximately 30% of its remaining performance obligations as revenue through 2019, an additional 40% through 2021, and the balance thereafter. Cumulative Catch-up Adjustments For the years ended December 31, 2018 , 2017 , and 2016 , net cumulative catch-up adjustments increased operating income by $110 million , $204 million , and $224 million , respectively, and increased diluted earnings per share by $1.99 , $2.90 , and $3.08 , respectively. Cumulative catch-up adjustments for the year ended December 31, 2016, included favorable adjustments of $74 million on a contract at the Ingalls segment, which increased diluted earnings per share by $1.02 . No individual adjustment was material to the Company's consolidated statements of operations and comprehensive income for the years ended December 31, 2018 and 2017 . Contract Balances Contract balances include accounts receivable, contract assets, and contract liabilities from contracts with customers. Accounts receivable represent an unconditional right to consideration and include amounts billed and currently due from customers. Contract assets primarily relate to the Company's rights to consideration for work completed but not billed as of the reporting date when the right to payment is not just subject to the passage of time. Fixed-price contracts are generally billed to the customer using either progress payments, whereby amounts are billed monthly as costs are incurred or work is completed, or performance based payments, which are based upon the achievement of specific, measurable events or accomplishments defined and valued at contract inception. Cost-type contracts are typically billed to the customer on a monthly or semi-monthly basis. Contract liabilities relate to advance payments, billings in excess of revenues, and deferred revenue amounts. The Company reports contract balances in a net contract asset or contract liability position on a contract-by-contract basis at the end of each reporting period. The Company’s net contract assets increased $59 million from December 31, 2017 to December 31, 2018 , primarily due to an increase in contract assets as a result of revenue on certain U.S. Navy contracts. For the year ended December 31, 2018 , the Company recognized revenue of $85 million related to its contract liabilities as of December 31, 2017 .

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Segment Information	SEGMENT INFORMATION The Company is organized into three reportable segments: Ingalls, Newport News, and Technical Solutions, consistent with how management makes operating decisions and assesses performance. U.S. Government Sales - Revenues from the U.S. Government include revenues from contracts for which HII is the prime contractor, as well as contracts for which the Company is a subcontractor and the ultimate customer is the U.S. Government. The Company derived over 95% of its revenues from the U.S. Government for each of the years ended December 31, 2018 , 2017 , and 2016 . Assets - Substantially all of the Company's assets are located or maintained in the United States. Results of Operations by Segment The following table presents the Company's operating results by segment. Year Ended December 31 ($ in millions) 2018 2017 2016 Sales and Service Revenues Ingalls $ 2,607 $ 2,420 $ 2,389 Newport News 4,722 4,164 4,089 Technical Solutions 988 952 691 Intersegment eliminations (141 ) (95 ) (101 ) Total sales and service revenues $ 8,176 $ 7,441 $ 7,068 Operating Income Ingalls $ 313 $ 313 $ 321 Newport News 318 354 386 Technical Solutions 32 21 8 Total segment operating income 663 688 715 Non-segment factors affecting operating income Operating FAS/CAS Adjustment 290 205 163 Non-current state income taxes (2 ) (12 ) (2 ) Total operating income $ 951 $ 881 $ 876 Sales transactions between segments are generally recorded at cost. Other Financial Information The following tables present the Company's assets, capital expenditures, and depreciation and amortization by segment. December 31 ($ in millions) 2018 2017 2016 Assets Ingalls $ 1,448 $ 1,385 1,362 Newport News 3,572 3,350 3,169 Technical Solutions 734 642 692 Corporate 629 997 1,129 Total assets $ 6,383 $ 6,374 $ 6,352 Year Ended December 31 ($ in millions) 2018 2017 2016 Capital Expenditures (1) Ingalls $ 134 $ 131 $ 97 Newport News 258 224 176 Technical Solutions 9 6 8 Corporate 1 — 4 Total capital expenditures $ 402 $ 361 $ 285 (1) Net of grant proceeds for capital expenditures Year Ended December 31 ($ in millions) 2018 2017 2016 Depreciation and Amortization (1) Ingalls $ 69 $ 73 $ 68 Newport News 113 107 109 Technical Solutions 21 25 9 Total depreciation and amortization $ 203 $ 205 $ 186 (1) Excluding amortization of debt issuance costs

Accounts Receivable and Contrac

Accounts Receivable and Contract Assets	12 Months Ended
	Dec. 31, 2018
Receivables [Abstract]
Accounts Receivable, Net	ACCOUNTS RECEIVABLE AND CONTRACT ASSETS Accounts Receivable Accounts receivable include amounts related to any unconditional Company right to receive consideration. Substantially all amounts included in accounts receivable as of December 31, 2018 , are expected to be collected in 2019 . Because the Company's accounts receivable are primarily with the U.S. Government or with companies acting as a contractor to the U.S. Government, the Company does not have material exposure to accounts receivable credit risk. Accounts receivable were comprised of the following: December 31 ($ in millions) 2018 2017 Due from U.S. Government $ 216 $ 275 Due from other customers 45 167 Total accounts receivable 261 442 Allowances for doubtful accounts (9 ) (13 ) Total accounts receivable, net $ 252 $ 429 Contract Assets Contract assets primarily relate to the Company’s rights to consideration for work completed but not billed as of the reporting date when the right to payment is not just subject to the passage of time. Contract assets include retention amounts, substantially all of which were under U.S. Government contracts. Contract assets were comprised of the following: December 31 ($ in millions) 2018 2017 Due from U.S. Government $ 899 $ 733 Due from other customers 104 26 Total contract assets 1,003 759

Inventoried Costs, Net

Inventoried Costs, Net	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Inventoried Costs, Net	INVENTORIED COSTS, NET Inventoried costs were comprised of the following: December 31 ($ in millions) 2018 2017 Production costs of contracts in process (1) $ 34 $ 90 Raw material inventory 94 93 Total inventoried costs, net $ 128 $ 183 (1) Includes amounts capitalized pursuant to applicable provisions of the FAR and CAS.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	GOODWILL AND OTHER INTANGIBLE ASSETS Goodwill HII performs impairment tests for goodwill as of November 30 of each year and between annual impairment tests if an event occurs or circumstances change that would more likely than not reduce the fair values of the Company's reporting units below their carrying values. Reporting units are aligned with the Company's businesses. The Company’s testing approach utilizes a combination of discounted cash flow analysis and comparative market multiples to determine the fair values of its businesses for comparison to their corresponding book values. In connection with the Company’s annual goodwill impairment tests as of November 30, 2018 , 2017, and 2016, management tested goodwill for each of its four reporting units. As a result of its annual goodwill impairment tests, the Company determined that the estimated fair value of each reporting unit exceeded by more than 10% its corresponding carrying value as of November 30, 2018 , 2017, and 2016. Accumulated goodwill impairment losses as of each of December 31, 2018 and 2017 , were $2,877 million . The accumulated goodwill impairment losses for Ingalls as of each of December 31, 2018 and 2017 , were $1,568 million . The accumulated goodwill impairment losses for Newport News as of each of December 31, 2018 and 2017 , were $1,187 million . The accumulated goodwill impairment losses for the Technical Solutions segment as of each of December 31, 2018 and 2017 , were $122 million . For the year ended December 31, 2017 , the Company recorded a goodwill adjustment of $17 million in the Technical Solutions segment, primarily driven by the finalization of fair value calculations for certain assets and liabilities, as well as the net working capital adjustment, related to the acquisition of Camber. For the years ended December 31, 2018 and 2017 , the carrying amounts of goodwill changed as follows: ($ in millions) Ingalls Newport News Technical Solutions Total Balance as of December 31, 2016 $ 175 $ 721 $ 338 $ 1,234 Adjustments — — (17 ) (17 ) Balance as of December 31, 2017 175 721 321 1,217 Acquisitions — — 46 46 Balance as of December 31, 2018 $ 175 $ 721 $ 367 $ 1,263 Other Intangible Assets The Company performs tests for impairment of long-lived assets whenever events or circumstances suggest that long-lived assets may be impaired. In connection with the G2 purchase in 2018, the Company recorded $20 million of intangible assets pertaining to existing contract backlog and customer relationships, to be amortized using the pattern of benefits method over a weighted-average life of seven years . In connection with the Camber purchase in 2016, the Company recorded $76 million of intangible assets pertaining to existing contract backlog and customer relationships, to be amortized using the pattern of benefits method over a weighted-average life of 10 years . The Company's purchased intangible assets are being amortized on a straight-line basis or a method based on the pattern of benefits over their estimated useful lives. Net intangible assets consist primarily of amounts pertaining to nuclear-powered aircraft carrier and submarine program intangible assets, with an aggregate weighted-average useful life of 40 years based on the long life cycle of the related programs. Aggregate amortization expense for the years ended December 31, 2018 , 2017 , and 2016 , was $36 million , $40 million , and $23 million , respectively. The Company expects amortization for purchased intangible assets of $37 million in 2019, $33 million in 2020, $30 million in 2021, $28 million in 2022, and $24 million in 2023.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES Tax Reform - The Tax Act, signed into law on December 22, 2017, significantly changed U.S. federal income tax law, including a provision that allows for full expensing of certain qualified property, reduction of the federal corporate income tax rate from 35% to 21% , repeal of the domestic manufacturing deduction, and further limitations on the deductibility of certain executive compensation. The SEC staff issued Staff Accounting Bulletin 118 ("SAB 118"), which provides guidance on accounting for the tax effects of the Tax Act in the reporting period of enactment, including a measurement period that should not extend beyond one year from the Tax Act enactment date for companies to complete the accounting under Accounting Standards Codification 740, Income Taxes. In accordance with SAB 118, a company must reflect the income tax effects of those aspects of the Tax Act for which the accounting under ASC 740 is complete. To the extent that a company’s accounting for certain income tax effects of the Tax Act is incomplete, but the company is able to determine a reasonable estimate, it must record a provisional estimate in the financial statements. If a company cannot determine a provisional estimate to be included in the financial statements, it should continue to apply ASC 740 on the basis of the provisions of the tax laws that were in effect immediately before enactment of the Tax Act. The Company's accounting for provisional adjustments for the following elements of the Tax Act was completed in 2018: Reduction of the U.S. federal corporate income tax rate: For the reduction in the federal corporate income tax rate, the Company recorded a provisional decrease in its deferred tax assets and deferred tax liabilities of $252 million and $196 million , respectively, with a corresponding net adjustment to deferred income tax expense of $56 million , for the year ended December 31, 2017. In October 2018, the Company received authorization from the Internal Revenue Service ("IRS") to change its accounting method for unbilled revenue related to service contracts effective January 1, 2017. As a result, the Company's provisional adjustment to its net deferred tax assets decreased by $10 million , with a corresponding reduction to deferred income tax expense of $10 million . This adjustment was recorded in the fourth quarter of 2018, which is the period in which authorization was received. Accounting for the reduction in the federal corporate income tax rate is now complete and resulted in recording a total decrease to net deferred tax assets of $46 million with a corresponding increase to deferred income tax expense. Acceleration of depreciation : For the acceleration of depreciation for assets qualifying for immediate expensing, the Company recorded a provisional benefit of $8 million for the year ended December 31, 2017, based on its intent to fully expense all qualifying expenditures. This resulted in a decrease of approximately $8 million to the Company's current income taxes payable and a corresponding decrease in its net deferred tax assets, excluding the effect of the reduction in the U.S. federal corporate income tax rate, for the year ended December 31, 2017. In preparing the Company’s consolidated federal income tax return, a detailed review of capital expenditures was completed. As a result of this analysis, the Company’s provisional benefit for asset expensing decreased by $4 million , resulting in an increase of $4 million to current income taxes payable and a corresponding increase in net deferred tax assets, which were recorded in the Company’s 2018 financial statements during the fourth quarter. Accounting for the acceleration of depreciation under the Tax Act is complete and resulted in a benefit of $4 million that decreased current income taxes payable, with a corresponding decrease in net deferred tax assets. The Company's accounting for the following element of the Tax Act, for which a reasonable estimate could not be made in the 2017 financial statements, was completed in 2018: Deductibility of executive compensation : As disclosed in the Company's Annual Report on Form 10-K for 2017, the Company was not able to reasonably estimate the effect of the Tax Act changes to the deductibility of executive compensation, and, therefore, no provisional adjustment was recorded. These changes included repeal of the performance-based compensation exception to the $1 million deduction limitation of Internal Revenue Code Section 162(m) and revision of the employees subject to the $1 million deduction limitation. The only exception to this rule is compensation paid pursuant to a binding contract in effect on November 2, 2017 that would have otherwise been deductible under prior Section 162(m) rules. Accordingly, any compensation paid in the future pursuant to compensation arrangements entered into after November 2, 2017, even if performance-based, will count toward the $1 million annual deduction limit if paid to an executive subject to Section 162(m). The Company completed its analysis of the binding contract requirement on its various compensation plans and determined the change on the deductibility of executive compensation did not have a material effect on the Company’s 2017 financial statements. Accordingly, no adjustment was required for this aspect of the Tax Act under ASC 740. The IRS did not issue guidance on all elements of the Tax Act in 2018. Accordingly, there remain certain elements of the Tax Act for which we cannot determine the full effects on our financial position, results of operations, or cash flows in future years. However, the Company does not expect these elements to have a material effect on the Company's financial position, results of operations, or cash flows in future years. The Company's earnings are primarily domestic, and its effective tax rate on earnings from operations for the year ended December 31, 2018 , was 13.9% , compared with 38.0% and 26.9% for 2017 and 2016 , respectively. For the year ended December 31, 2018 , the Company's effective tax rate differed from the federal statutory tax rate primarily as a result of claims for higher research and development tax credits for prior tax years. For the year ended December 31, 2017 , the Company's effective tax rate differed from the federal statutory rate primarily as a result of the increase in deferred federal tax expense attributable to the recalculation of the Company's net deferred tax asset to reflect the impact of the federal income tax rate decrease included in the Tax Act, partially offset by the income tax benefits resulting from stock award settlement activity and the domestic manufacturing deduction. For the year ended December 31, 2016 , the Company’s effective tax rate differed from the federal statutory rate primarily as a result of the adoption of ASU 2016-09, which reduced income tax expense by the income tax benefits resulting from stock award settlement activity, a remeasurement of uncertain tax positions that resulted in a decrease in cumulative unrecognized tax benefits, and the domestic manufacturing deduction. Adoption of ASU 2018-02 - The Company early adopted ASU 2018-02, "Income Statement-Reporting Comprehensive Income (Topic 220), Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income," which provides for the reclassification from accumulated other comprehensive loss to retained earnings of stranded tax effects resulting from the Tax Act. In accordance with the provisions of the ASU, $202 million of stranded tax effects related to the Tax Act were reclassified from accumulated other comprehensive loss to retained earnings in the first quarter of 2018. This reclassification includes the impact of the change in the federal corporate income tax rate and the related federal benefit of state taxes. Non-current state income taxes include deferred state income taxes, which reflect the change in deferred state tax assets and liabilities, and the tax expense or benefit associated with changes in state uncertain tax positions in the relevant period. These amounts are recorded within operating income. Current period state income tax expense is charged to contract costs and included in cost of sales and service revenues in segment operating income. In connection with the spin-off from Northrop Grumman, HII entered into a Tax Matters Agreement with Northrop Grumman, which governs the respective rights, responsibilities, and obligations of Northrop Grumman and the Company with respect to tax liabilities and benefits, tax attributes, tax contests, and other tax sharing regarding U.S. federal, state, local, and foreign income taxes, other taxes, and related tax returns. The Company is severally liable with Northrop Grumman for its income taxes for periods before the spin-off. HII is obligated to indemnify Northrop Grumman for tax adjustments that increase the Company's taxable income for periods before the spin-off and are of a nature that could result in a correlative reduction in HII's taxable income for periods after the spin-off. Northrop Grumman is obligated to indemnify HII for tax adjustments that decrease the Company's taxable income for periods before the spin-off and are of a nature that could result in a correlative increase in HII's taxable income for periods after the spin-off. These payment obligations only apply once the aggregate tax liability related to tax adjustments exceeds $5 million . Once the aggregate amount is exceeded, only the amount in excess of $5 million is ultimately required to be paid. In 2016 and prior years, HII incurred non-cash federal and state tax adjustments for items governed by the Tax Matters Agreement. The federal tax expense (benefit) adjustment is reported as a component of tax expense, while the state tax expense (benefit) adjustment is treated as an allowable cost in the applicable period under the terms of the Company's existing contracts and is included in general and administrative expenses. In 2016, Northrop Grumman settled with the IRS for the years 2007 through the date of the spin-off, during which HII was part of its consolidated tax returns. Northrop Grumman’s 2007 through 2011 federal tax returns are currently subject to examination due to the filing of refund claims for those years. As of December 31, 2017 , the Company was due $8 million from Northrop Grumman under spin-off related agreements, including the Tax Matters Agreement. For the year ended December 31, 2018 , the Company received the $8 million from Northrop Grumman. The Company does not anticipate there will be any additional amounts owed between HII and Northrop Grumman under the Tax Matters Agreement in future years. Federal and foreign income tax expense for the years ended December 31, 2018 , 2017 , and 2016 , consisted of the following: Year Ended December 31 ($ in millions) 2018 2017 2016 Income Taxes on Operations Federal and foreign income taxes currently payable $ 127 $ 121 $ 134 Change in deferred federal and foreign income taxes 8 172 77 Total federal and foreign income taxes $ 135 $ 293 $ 211 Earnings and income tax from foreign operations are not material for any periods presented. Income tax expense differed from the amount based on the statutory federal income tax rate applied to earnings (loss) before income taxes due to the following: Year Ended December 31 ($ in millions) 2018 2017 2016 Income tax expense (benefit) on operations at statutory rate $ 204 $ 270 $ 274 Provisional deferred tax asset revaluation - Tax Act (10 ) 56 — Stock compensation - net excess tax benefits (5 ) (25 ) (29 ) Manufacturing deduction — (12 ) (21 ) Uncertain tax positions 25 — (15 ) Research and development tax credit (80 ) — — Other, Net 1 4 2 Total federal and foreign income taxes $ 135 $ 293 $ 211 Unrecognized Tax Benefits - Unrecognized tax benefits represent the gross value of the Company's uncertain tax positions that have not been reflected in the consolidated statements of operations. If the income tax benefits from federal tax positions are ultimately realized, such realization would affect the Company's income tax expense, while the realization of state tax benefits would be recorded in general and administrative expenses. The changes in unrecognized tax benefits (exclusive of interest and penalties) for the years ended December 31, 2018 , 2017 , and 2016 are summarized in the following table: December 31 ($ in millions) 2018 2017 2016 Unrecognized tax benefits at beginning of the year $ — $ 2 $ 27 Additions based on tax positions related to the current year 3 — 1 Additions based on tax positions related to prior years 22 — 2 Reductions based on tax positions related to prior years — — (15 ) Settlements — — (11 ) Statute of limitation expirations — (2 ) (2 ) Net change in unrecognized tax benefits 25 (2 ) (25 ) Unrecognized tax benefits at end of the year $ 25 $ — 2 As of December 31, 2018 and 2017 , the estimated amounts of the Company's uncertain tax positions, excluding interest and penalties, were liabilities of $25 million and less than $1 million, respectively. Assuming sustainment of these positions, as of December 31, 2018 and 2017 , the reversal of $25 million and less than $1 million , respectively, of the amounts accrued would favorably affect the Company's effective federal income tax rate in future periods. The Company recognizes interest and penalties related to unrecognized tax benefits as income tax expense. As a result of the unrecognized tax benefits noted above, income tax expense increased $1 million in 2018 for interest and penalties, resulting in a liability of $1 million for interest and penalties as of December 31, 2018 . In 2017 , there was a net decrease in income tax expense of $1 million for interest and penalties, resulting in no material liability for interest and penalties as of December 31, 2017 . The 2017 changes in interest and penalties related to statute of limitation expirations. In 2016 , there was a net decrease in income tax expense of $2 million for interest and penalties, resulting in a total liability of $1 million for interest and penalties as of December 31, 2016 . The 2016 changes in interest and penalties related to reductions in prior year tax positions and settlement with a taxing authority. The following table summarizes the tax years that are either currently under examination or remain open under the applicable statute of limitations and subject to examination by the major tax jurisdictions in which the Company operates: Jurisdiction Years United States (1) 2011 - 2017 Connecticut 2016 - 2017 Mississippi 2012 - 2017 Virginia (1) 2011 - 2017 (1) The 2014 tax year has been closed in these jurisdictions. Although the Company believes it has adequately provided for all uncertain tax positions, amounts asserted by taxing authorities could be greater than the Company's accrued position. Accordingly, additional provisions for federal and state income tax related matters could be recorded in the future as revised estimates are made or the underlying matters are effectively settled or otherwise resolved. Conversely, the Company could settle positions with the tax authorities for amounts lower than have been accrued. The Company believes that it is reasonably possible that during the next 12 months the Company's liability for uncertain tax positions may decrease by $14 million due to resolution of a federal uncertain tax position. During 2013 the Company entered into the pre-Compliance Assurance Process with the IRS for years 2011 and 2012. The Company is part of the IRS Compliance Assurance Process program for the 2014 through 2018 tax years. Open tax years related to state jurisdictions remain subject to examination. Deferred Income Taxes - Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and for income tax purposes. As described above, deferred tax assets and liabilities are calculated as of the balance sheet date using current tax laws and rates expected to be in effect when the deferred tax items reverse in future periods. As a result of the reduction in the corporate income tax rate from 35% to 21% under the Tax Act, the Company revalued its net deferred tax assets as of December 31, 2017. Net deferred tax assets are classified as long-term deferred tax assets in the consolidated statements of financial position. The tax effects of significant temporary differences and carry-forwards that gave rise to year-end deferred tax balances, as presented in the consolidated statements of financial position, were as follows: December 31 ($ in millions) 2018 2017 Deferred Tax Assets Retirement benefits $ 331 $ 263 Workers' compensation 151 167 Reserves not currently deductible for tax purposes 52 44 Stock-based compensation 10 11 Net operating losses and tax credit carry-forwards 19 21 Other 5 — Gross deferred tax assets 568 506 Less valuation allowance 12 12 Net deferred tax assets 556 494 Deferred Tax Liabilities Depreciation and amortization 247 223 Contract accounting differences 43 51 Purchased intangibles 103 106 Gross deferred tax liabilities 393 380 Total net deferred tax assets $ 163 $ 114 As of December 31, 2018 , the Company had gross state income tax credit carry-forwards of approximately $20 million , which expire from 2019 through 2021. A deferred tax asset of approximately $15 million (net of federal benefit) has been established related to these state income tax credit carry-forwards, with a valuation allowance of $9 million against such deferred tax asset as of December 31, 2018 . State and foreign net operating loss carry-forwards are separately and cumulatively immaterial to the Company’s deferred tax balances and expire between 2026 and 2037.

Debt

Debt	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt	DEBT Long-term debt consisted of the following: December 31 ($ in millions) 2018 2017 Senior notes due November 15, 2025, 5.000% 600 600 Senior notes due December 1, 2027, 3.483% 600 600 Mississippi economic development revenue bonds due May 1, 2024, 7.81% 84 84 Gulf opportunity zone industrial development revenue bonds due December 1, 2028, 4.55% 21 21 Less unamortized debt issuance costs (22 ) (26 ) Total long-term debt 1,283 1,279 Credit Facility - In November 2017, the Company terminated its Second Amended and Restated Credit Agreement and entered into a new Credit Agreement (the "Credit Facility") with third-party lenders. The Credit Facility includes a revolving credit facility of $1,250 million , which may be drawn upon during a period of five years from November 22, 2017. The revolving credit facility includes a letter of credit subfacility of $500 million . The revolving credit facility has a variable interest rate on outstanding borrowings based on the London Interbank Offered Rate ("LIBOR") plus a spread based upon the Company's credit ratings, which may vary between 1.125% and 1.500% . The revolving credit facility also has a commitment fee rate on the unutilized balance based on the Company’s credit ratings. The commitment fee rate as of December 31, 2018 was 0.25% and may vary between 0.20% and 0.30% . The Credit Facility contains customary affirmative and negative covenants, as well as a financial covenant based on a maximum total leverage ratio. Each of the Company's existing and future material wholly owned domestic subsidiaries, except those that are specifically designated as unrestricted subsidiaries, are and will be guarantors under the Credit Facility. As of December 31, 2018 , approximately $16 million in letters of credit were issued but undrawn, and the remaining $1,234 million of the revolving credit facility was unutilized. The Company had unamortized debt issuance costs associated with its credit facilities of $8 million and $11 million as of December 31, 2018 and 2017 , respectively. Senior Notes - In December 2017, the Company issued $600 million aggregate principal amount of 3.483% senior notes with registration rights due December 2027, the net proceeds of which were used to repurchase the Company's 5.000% senior notes due 2021. Pursuant to the terms of the registration rights agreement entered into in connection with the issuance of these senior notes, the Company completed in June 2018 an exchange of $600 million aggregate principal amount of registered 3.483% senior notes due December 2027 for all of the then outstanding unregistered senior notes due December 2027. The Company also has outstanding $600 million aggregate principal amount of unregistered 5.000% senior notes due November 2025. Interest on the Company's senior notes is payable semi-annually. The terms of the senior notes limit the Company’s ability and the ability of certain of its subsidiaries to create liens, enter into sale and leaseback transactions, sell assets, and effect consolidations or mergers. The Company had unamortized debt issuance costs associated with the senior notes of $14 million and $15 million as of December 31, 2018 and 2017 , respectively. Early Extinguishment of Debt - Details of the loss on early extinguishment of debt related to the Company's prior credit facility and refinancing of senior notes, which was included in interest expense, were as follows: Year Ended ($ in millions) December 31, 2017 Redemption and tender premiums and fees $ 15 Write-off of unamortized debt issuance costs 7 Total loss on early extinguishment of debt $ 22 Mississippi Economic Development Revenue Bonds - As of each of December 31, 2018 and 2017 , the Company had $84 million outstanding under Industrial Revenue Bonds issued by the Mississippi Business Finance Corporation. These bonds accrue interest at a fixed rate of 7.81% per annum (payable semi-annually) and mature in 2024. Gulf Opportunity Zone Industrial Development Revenue Bonds - As of each of December 31, 2018 and 2017 , the Company had $21 million outstanding under Gulf Opportunity Zone Industrial Development Revenue Bonds issued by the Mississippi Business Finance Corporation. These bonds accrue interest at a fixed rate of 4.55% per annum (payable semi-annually) and mature in 2028. The Company's debt arrangements contain customary affirmative and negative covenants. The Company was in compliance with all debt covenants during the year ended December 31, 2018 . The estimated fair values of the Company's total long-term debt as of December 31, 2018 , and December 31, 2017 , were $1,292 million and $1,361 million , respectively. The fair values of the Company's long-term debt were calculated based on recent trades of the Company's debt instruments in inactive markets, which fall within Level 2 under the fair value hierarchy. The Company does not have any principal payments due on long-term debt within the next five years.

Investigations, Claims, And Lit

Investigations, Claims, And Litigation	12 Months Ended
	Dec. 31, 2018
Investigations, Claims, And Litigation [Abstract]
Investigations, Claims, And Litigation	INVESTIGATIONS, CLAIMS, AND LITIGATION The Company is involved in legal proceedings before various courts and administrative agencies, and is periodically subject to government examinations, inquiries and investigations. Pursuant to FASB Accounting Standards Codification 450 Contingencies, the Company has accrued for losses associated with investigations, claims, and litigation when, and to the extent that, loss amounts related to the investigations, claims, and litigation are probable and can be reasonably estimated. The actual losses that might be incurred to resolve such investigations, claims, and litigation may be higher or lower than the amounts accrued. For matters where a material loss is probable or reasonably possible and the amount of loss cannot be reasonably estimated, but the Company is able to reasonably estimate a range of possible losses, the Company will disclose such estimated range in these notes. This estimated range is based on information currently available to the Company and involves elements of judgment and significant uncertainties. Any estimated range of possible loss does not represent the Company's maximum possible loss exposure. For matters as to which the Company is not able to reasonably estimate a possible loss or range of loss, the Company will indicate the reasons why it is unable to estimate the possible loss or range of loss. For matters not specifically described in these notes, the Company does not believe, based on information currently available to it, that it is reasonably possible that the liabilities, if any, arising from such investigations, claims, and litigation will have a material effect on its consolidated financial position, results of operations, or cash flows. The Company has, in certain cases, provided disclosure regarding certain matters for which the Company believes at this time that the likelihood of material loss is remote. False Claims Act Complaint - In 2015, the Company received a Civil Investigative Demand from the Department of Justice ("DoJ") relating to an investigation of certain allegedly non-conforming parts the Company purchased from one of its suppliers for use in connection with U.S. Government contracts. The Company has cooperated with the DoJ in connection with its investigation. In 2016, the Company was made aware that it is a defendant in a False Claims Act lawsuit filed under seal in the U.S. District Court for the Middle District of Florida related to the Company’s purchases of the allegedly non-conforming parts from the supplier. Depending upon the outcome of this matter, the Company could be subject to civil penalties, damages, and/or suspension or debarment from future U.S. Government contracts, which could have a material adverse effect on its consolidated financial position, results of operations, or cash flows. The matter remains sealed and given the current posture of the matter, the Company is unable to estimate an amount or range of reasonably possible loss or to express an opinion regarding the ultimate outcome. U.S. Government Investigations and Claims - Departments and agencies of the U.S. Government have the authority to investigate various transactions and operations of the Company, and the results of such investigations may lead to administrative, civil or criminal proceedings, the ultimate outcome of which could be fines, penalties, repayments or compensatory, treble, or other damages. U.S. Government regulations provide that certain findings against a contractor may also lead to suspension or debarment from future U.S. Government contracts or the loss of export privileges. Any suspension or debarment would have a material effect on the Company because of its reliance on government contracts. Asbestos Related Claims - HII and its predecessors-in-interest are defendants in a longstanding series of cases that have been and continue to be filed in various jurisdictions around the country, wherein former and current employees and various third parties allege exposure to asbestos containing materials while on or associated with HII premises or while working on vessels constructed or repaired by HII. The cases allege various injuries, including those associated with pleural plaque disease, asbestosis, cancer, mesothelioma, and other alleged asbestos related conditions. In some cases, several of HII's former executive officers are also named as defendants. In some instances, partial or full insurance coverage is available to the Company for its liability and that of its former executive officers. The cost to resolve cases during the years ended December 31, 2018 , 2017 , and 2016 was immaterial individually and in the aggregate. The Company’s estimate of asbestos-related liabilities is subject to uncertainty because liabilities are influenced by numerous variables that are inherently difficult to predict. Key variables include the number and type of new claims, the litigation process from jurisdiction to jurisdiction and from case to case, reforms made by state and federal courts, and the passage of state or federal tort reform legislation. Although the Company believes the ultimate resolution of current cases will not have a material effect on its consolidated financial position, results of operations, or cash flows, it cannot predict what new or revised claims or litigation might be asserted or what information might come to light and can therefore give no assurances regarding the ultimate outcome of asbestos related litigation. Other Litigation - The Company and its predecessor-in-interest have been in litigation with the Bolivarian Republic of Venezuela (the "Republic") since 2002 over a contract for the repair, refurbishment, and modernization at Ingalls of two foreign-built frigates. The case proceeded towards arbitration, then appeared to settle favorably, but the settlement was overturned in court and the matter returned to litigation. In March 2014, the Company filed an arbitral statement of claim asserting breaches of the contract. In July 2014, the Republic filed a statement of defense in the arbitration denying all the Company’s allegations and a counterclaim alleging late redelivery of the frigates, unfinished work, and breach of warranty. In February 2018, the arbitral tribunal awarded the Company approximately $151 million on its claims and awarded the Republic approximately $22 million on its counterclaims. The Company has filed a petition in the United States District Court for the District of Columbia asking the court to confirm or enforce the award. No assurances can be provided regarding the ultimate resolution of this matter. The Company is party to various other claims, legal proceedings, and investigations that arise in the ordinary course of business, including U.S. Government investigations that could result in administrative, civil, or criminal proceedings involving the Company. The Company is a contractor with the U.S. Government, and such proceedings could therefore include additional False Claims Act allegations against the Company. Although the Company believes that the resolution of these other claims, legal proceedings, and investigations will not have a material effect on its consolidated financial position, results of operations, or cash flows, the Company cannot predict what new or revised claims or litigation might be asserted or what information might come to light and can, therefore, give no assurances regarding the ultimate outcome of these matters.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Contract Performance Contingencies - Contract profit margins may include estimates of revenues for matters on which the customer and the Company have not reached agreement, such as settlements in the process of negotiation, contract changes, claims, and requests for equitable adjustment for unanticipated contract costs. These estimates are based upon management's best assessment of the underlying causal events and circumstances, and are included in contract profit margins to the extent of expected recovery based upon contractual entitlements and the probability of successful negotiation with the customer. As of December 31, 2018 , recognized amounts related to claims and requests for equitable adjustment were not material individually or in aggregate. Guarantees of Performance Obligations - From time to time in the ordinary course of business, HII may enter into joint ventures, teaming, and other business arrangements to support the Company's products and services. The Company attempts to limit its exposure under these arrangements to its investment or the extent of obligations under the applicable contract. In some cases, however, HII may be required to guarantee performance of the arrangement's obligations and, in such cases, generally obtains cross-indemnification from the other members of the arrangement. In the ordinary course of business, the Company may guarantee obligations of its subsidiaries under certain contracts. Generally, the Company is liable under such an arrangement only if its subsidiary is unable to perform its obligations. Historically, the Company has not incurred any substantial liabilities resulting from these guarantees. As of December 31, 2018 , the Company was not aware of any existing event of default that would require it to satisfy any of these guarantees. Environmental Matters - The estimated cost to complete environmental remediation has been accrued when it is probable that the Company will incur such costs in the future to address environmental conditions at currently or formerly owned or leased operating facilities, or at sites where it has been named a Potentially Responsible Party ("PRP") by the Environmental Protection Agency or similarly designated by another environmental agency, and the related costs can be estimated by management. These accruals do not include any litigation costs related to environmental matters, nor do they include amounts recorded as asset retirement obligations. To assess the potential impact on the Company's consolidated financial statements, management estimates the range of reasonably possible remediation costs that could be incurred by the Company, taking into account currently available facts on each site, as well as the current state of technology and prior experience remediating contaminated sites. These estimates are reviewed periodically and adjusted to reflect changes in facts and technical and legal circumstances. Management estimates that as of December 31, 2018 , the probable estimable future cost for environmental remediation was immaterial. Factors that could result in changes to the Company's estimates include: modification of planned remedial actions, increases or decreases in the estimated time required to remediate, changes to the determination of legally responsible parties, discovery of more extensive contamination than anticipated, changes in laws and regulations affecting remediation requirements, and improvements in remediation technology. Should other PRPs not pay their allocable share of remediation costs, the Company may incur costs exceeding those already estimated and accrued. In addition, there are certain potential remediation sites where the costs of remediation cannot be reasonably estimated. Although management cannot predict whether new information gained as remediation progresses will materially affect the estimated liability accrued, management does not believe that future remediation expenditures will have a material effect on the Company's consolidated financial position, results of operations, or cash flows. Financial Arrangements - In the ordinary course of business, HII uses standby letters of credit issued by commercial banks and surety bonds issued by insurance companies primarily to support the Company's self-insured workers' compensation plans. As of December 31, 2018 , the Company had $16 million in standby letters of credit issued but undrawn, as indicated in Note 14: Debt, and $275 million of surety bonds outstanding. U.S. Government Claims - From time to time, the U.S. Government communicates to the Company potential claims, disallowed costs, and penalties concerning prior costs incurred by the Company with which the U.S. Government disagrees. When such preliminary findings are presented, the Company and U.S. Government representatives engage in discussions, from which HII evaluates the merits of the claims and assesses the amounts being questioned. Although the Company believes that the resolution of any of these matters will not have a material effect on its consolidated financial position, results of operations, or cash flows, it cannot predict the ultimate outcome of these matters. In February 2018, the Company received the findings of an audit conducted by the Defense Contract Audit Agency ("DCAA") citing potentially significant deficiencies in the Company’s Newport News segment's business system for material management. The Company submitted a response in June 2018, agreeing in part and disagreeing in part with the audit findings, and the Company and the U.S. Government continue to engage in discussions regarding the accuracy and significance of the DCAA’s findings. In the event the U.S. Government makes a final determination that there are remaining significant deficiencies and that the Company’s proposed corrective actions are inadequate, the U.S. Government may withhold up to 5% from the Company’s interim billings on cost-reimbursement, labor-hour, and time and materials contracts at Newport News containing the applicable contractor business systems clause, until the U.S. Government determines all significant deficiencies have been remediated. All U.S. Government contracts at the Newport News segment contain the relevant business systems provision, and any related withholding could have a material impact on the timing of the Company’s cash receipts. Collective Bargaining Agreements - Of the Company's approximately 40,000 employees, approximately 50% are covered by a total of nine collective bargaining agreements and two site stabilization agreements. Newport News has four collective bargaining agreements covering represented employees, which expire in December 2019, November 2020, November 2021, and December 2022. The collective bargaining agreement that expires in November 2021 covers approximately 50% of Newport News employees. Newport News craft workers employed at the Kesselring Site near Saratoga Springs, New York are represented under an indefinite Department of Energy ("DoE") site agreement. Ingalls has five collective bargaining agreements covering represented employees, all of which expire in March 2022. Approximately 35 Technical Solutions craft employees at the Hanford Site near Richland, Washington are represented under an indefinite DoE site stabilization agreement. The Company believes its relationship with its employees is satisfactory. Collective bargaining agreements generally expire after three to five years and are subject to renegotiation at that time. The Company does not expect the results of these negotiations, either individually or in the aggregate, to have a material effect on the Company's consolidated results of operations. Purchase Obligations - Periodically the Company enters into agreements to purchase goods or services that are enforceable and legally binding on the Company and specify all significant terms, including: fixed or minimum quantities to be purchased; fixed, minimum, or variable price provisions; and the approximate timing of the transaction. These obligations are primarily comprised of open purchase order commitments to vendors and subcontractors pertaining to funded contracts. Operating Leases - Rental expense for operating leases for the years ended December 31, 2018 , 2017 , and 2016 , was $69 million , $63 million , and $69 million , respectively. These amounts are net of immaterial amounts of sublease rental income. The amounts of minimum rental commitments under long-term non-cancellable operating leases for each of the years 2019 through 2023 and thereafter are: ($ in millions) 2019 $ 41 2020 36 2021 30 2022 20 2023 13 Thereafter 56 Total $ 196

Employee Pension and Other Post

Employee Pension and Other Postretirement Benefits	12 Months Ended
	Dec. 31, 2018
Retirement Benefits [Abstract]
Employee Pension and Other Postretirement Benefits	EMPLOYEE PENSION AND OTHER POSTRETIREMENT BENEFITS The Company provides eligible employees defined benefit pension plans and postretirement benefit plans. Non-collectively bargained defined benefit pension benefits accruing under the traditional years of service and compensation formula were amended in 2009 to freeze future service accruals and have been replaced with a cash balance benefit for all current non-collectively bargained employees. Except for the major collectively bargained plan at Ingalls, the Company's qualified defined benefit pension plans are frozen to new entrants. The Company's policy is to fund its qualified defined benefit pension plans at least to the minimum amounts required under U.S. Government regulations. Plan obligations are measured based on the present value of projected future benefit payments to participants for services rendered to date. The measurement of projected future benefits is dependent on the terms of each individual plan, demographics, and valuation assumptions. No assumption is made regarding any potential changes to the benefit provisions beyond those to which the Company is currently committed, for example under existing collective bargaining agreements. The Company also sponsors 401(k) defined contribution pension plans in which most employees, including certain hourly employees, are eligible to participate. Company contributions for most defined contribution pension plans are based on the matching of employee contributions up to 4% of eligible compensation. Certain hourly employees are covered under a target benefit plan. In addition to the 401(k) defined contribution pension benefit formula, non-collectively bargained employees hired after June 30, 2008, are eligible to participate in a defined contribution benefit program in lieu of a defined benefit pension plan. The Company's contributions to the qualified defined contribution pension plans for the years ended December 31, 2018 , 2017 , and 2016 , were $102 million , $78 million , and $71 million , respectively. The Company also sponsors defined benefit and defined contribution pension plans to provide benefits in excess of the tax-qualified limits. The liabilities related to these plans as of December 31, 2018 , were $183 million and $30 million , respectively, and as of December 31, 2017 , were $182 million and $32 million , respectively. Assets, primarily in the form of Level 1 marketable securities held in grantor trusts, are intended to fund certain of these obligations. The trusts’ fair values supporting these liabilities as of December 31, 2018 and 2017 , were $109 million and $94 million , respectively, of which $78 million and $61 million , respectively, were related to the non-qualified defined benefit pension plans. The Company provides contributory postretirement health care and life insurance benefits to a dominantly closed group of eligible employees, retirees, and their qualifying dependents. Covered employees achieve eligibility to participate in these contributory plans upon retirement from active service if they meet specified age, years of service, and grandfathered requirements. Benefits are not guaranteed, and the Company reserves the right to amend or terminate coverage at any time. The Company's contributions for retiree health care benefits are subject to caps, which limit Company contributions when spending thresholds are reached. The measurement date for all of the Company's retirement related plans is December 31. The costs of the Company's defined benefit pension plans and other postretirement benefit plans for the years ended December 31, 2018 , 2017 , and 2016 , were as follows: Pension Benefits Other Benefits Year Ended December 31 Year Ended December 31 ($ in millions) 2018 2017 2016 2018 2017 2016 Components of Net Periodic Benefit Cost Service cost $ 157 $ 146 $ 133 $ 8 $ 10 $ 10 Interest cost 254 266 262 21 24 25 Expected return on plan assets (429 ) (367 ) (346 ) — — — Amortization of prior service cost (credit) 24 20 18 (22 ) (20 ) (19 ) Amortization of net actuarial loss (gain) 81 97 84 (3 ) (4 ) (6 ) Net periodic benefit cost $ 87 $ 162 $ 151 $ 4 $ 10 $ 10 The funded status of these plans as of December 31, 2018 and 2017 , was as follows: Pension Benefits Other Benefits December 31 December 31 ($ in millions) 2018 2017 2018 2017 Change in Benefit Obligation Benefit obligation at beginning of year $ 6,778 $ 6,050 $ 553 $ 578 Service cost 157 146 8 10 Interest cost 254 266 21 24 Plan participants' contributions 6 4 8 8 Plan amendments — 74 — (10 ) Actuarial loss (gain) (441 ) 457 (73 ) (15 ) Benefits paid (235 ) (219 ) (38 ) (42 ) Benefit obligation at end of year 6,519 6,778 479 553 Change in Plan Assets Fair value of plan assets at beginning of year 5,837 4,911 — — Actual return on plan assets (398 ) 840 — — Employer contributions 516 301 30 34 Plan participants' contributions 6 4 8 8 Benefits paid (235 ) (219 ) (38 ) (42 ) Fair value of plan assets at end of year 5,726 5,837 — — Funded status $ (793 ) $ (941 ) $ (479 ) $ (553 ) Amounts Recognized in the Consolidated Statements of Financial Position: Pension plan assets (1) $ — $ 6 $ — $ — Current liability (2) (29 ) (25 ) (131 ) (139 ) Non-current liability (3) (764 ) (922 ) (348 ) (414 ) Accumulated other comprehensive loss (income) (pre-tax) related to: Prior service costs (credits) 99 122 (53 ) (75 ) Net actuarial loss (gain) 1,780 1,477 (88 ) (18 ) (1) Included in miscellaneous other assets. (2) Included in other current liabilities and current portion of postretirement plan liabilities, respectively. (3) Included in pension plan liabilities and other postretirement plan liabilities, respectively. The Projected Benefit Obligation ("PBO"), Accumulated Benefit Obligation ("ABO"), and asset values for the Company's qualified pension plans were $6,336 million , $6,017 million , and $5,726 million , respectively, as of December 31, 2018 , and $6,596 million , $6,202 million , and $5,837 million , respectively, as of December 31, 2017 . The PBO represents the present value of pension benefits earned through the end of the year, with allowance for future salary increases. The ABO is similar to the PBO, but does not provide for future salary increases. The PBO and fair value of plan assets for all qualified and non-qualified pension plans with PBOs in excess of plan assets were $6,519 million and $5,726 million , respectively, as of December 31, 2018 , and $5,386 million and $4,440 million , respectively, as of December 31, 2017 . The ABO and fair value of plan assets for all qualified and non-qualified pension plans with ABOs in excess of plan assets were $6,183 million and $5,726 million , respectively, as of December 31, 2018 , and $5,001 million and $4,440 million , respectively, as of December 31, 2017 . The ABO for all pension plans was $6,183 million and $6,367 million as of December 31, 2018 and 2017 , respectively. The changes in amounts recorded in accumulated other comprehensive income (loss) were as follows: Pension Benefits Other Benefits Year Ended December 31 Year Ended December 31 ($ in millions) 2018 2017 2016 2018 2017 2016 Prior service cost (credit) $ — $ (74 ) $ — $ — $ 10 $ — Amortization of prior service cost (credit) 24 20 18 (22 ) (20 ) (19 ) Net actuarial loss (gain) (386 ) 16 (241 ) 73 15 (9 ) Amortization of net actuarial loss (gain) 81 97 84 (3 ) (4 ) (6 ) Other 1 (1 ) 1 — — — Total changes in accumulated other comprehensive income (loss) $ (280 ) $ 58 $ (138 ) $ 48 $ 1 $ (34 ) The amounts included in accumulated other comprehensive income (loss) as of December 31, 2018 , expected to be recognized as components of net periodic expense in 2019 are as follows: ($ in millions) Pension Benefits Other Benefits Prior service cost (credit) $ 18 $ (22 ) Net loss 113 (11 ) Total $ 131 $ (33 ) The weighted average assumptions used to determine the net periodic benefit costs for each year ended December 31 were as follows: Pension Benefits 2018 2017 2016 Discount rate 3.82 % 4.47 % 4.73 % Expected long-term rate on plan assets 7.25 % 7.25 % 7.50 % Rate of compensation increase 3.71 % 3.68 % 3.66 % Other Benefits 2018 2017 2016 Discount rate 3.85 % 4.38 % 4.58 % Initial health care cost trend rate assumed for next year 6.00 % 6.50 % 7.00 % Gradually declining to a rate of 4.50 % 5.00 % 5.00 % Year in which the rate reaches the ultimate rate 2025 2025 2024 The weighted average assumptions used to determine the benefit obligations as of December 31 of each year were as follows: Pension Benefits Other Benefits December 31 December 31 2018 2017 2018 2017 Discount rate 4.34 % 3.82 % 4.33 % 3.85 % Rate of compensation increase 3.67 % 3.71 % Initial health care cost trend rate assumed for next year 5.50 % 6.00 % Gradually declining to a rate of 4.50 % 4.50 % Year in which the rate reaches the ultimate rate 2024 2025 Health Care Cost Trend Rate - The health care cost trend rate represents the annual rates of change in the cost of health care benefits based on estimates of health care inflation, changes in health care utilization or delivery patterns, technological advances, government mandated benefits, and other considerations. Using a combination of market expectations and economic projections on December 31, 2018 , the Company selected an expected initial health care cost trend rate of 5.50% and an ultimate health care cost trend rate of 4.50% to be reached in 2024 . On December 31, 2017 , the Company assumed an expected initial health care cost trend rate of 6.00% and an ultimate health care cost trend rate of 4.50% to be reached in 2025 . A one percent change in the assumed health care cost trend rates would have the following effects on 2018 results: 1 Percentage Point ($ in millions) Increase Decrease Effect on postretirement benefit expense $ 2 $ (2 ) Effect on postretirement benefit obligations 22 (20 ) The Employee Retirement Income Security Act of 1974 ("ERISA"), including amendments under pension relief, defines the minimum amount that must be contributed to the Company's qualified defined benefit pension plans. In determining whether to make discretionary contributions to these plans above the minimum required amounts, the Company considers various factors, including attainment of the funded percentage needed to avoid benefit restrictions and other adverse consequences, minimum CAS funding requirements, and the current and anticipated future funding levels of each plan. The Company's contributions to its qualified defined benefit pension plans are affected by a number of factors, including published IRS interest rates, the actual return on plan assets, actuarial assumptions, and demographic experience. These factors and the Company's resulting contributions also impact the funded status of each plan. The Company made the following contributions to its pension plans and other postretirement plans for the years ended December 31, 2018 , 2017 , and 2016 : Year Ended December 31 ($ in millions) 2018 2017 2016 Pension plans Discretionary Qualified $ 508 $ 294 $ 167 Non-qualified 8 7 6 Other benefit plans 30 34 32 Total contributions $ 546 $ 335 $ 205 For the year ending December 31, 2019 , the Company expects its cash contributions to its qualified defined benefit pension plans to be $21 million , all of which will be discretionary. For the year ending December 31, 2019 , the Company expects its cash contributions to its postretirement benefit plans to be approximately $33 million . The following table presents estimated future benefit payments, using the same assumptions used in determining the Company's benefit obligations as of December 31, 2018 . Benefit payments depend on future employment and compensation levels, years of service, and mortality. Changes in any of these factors could significantly affect these estimated amounts. Other Benefits ($ in millions) Pension Benefits Benefit Payments Subsidy Receipts 2019 $ 254 $ 33 $ — 2020 266 35 — 2021 285 37 — 2022 306 37 — 2023 326 38 — Years 2024 to 2028 $ 1,927 $ 181 $ 2 Pension Plan Assets Pension assets include public equities, government and corporate bonds, cash and cash equivalents, private real estate funds, private partnerships, hedge funds, and other assets. Plan assets are held in a master trust and overseen by the Company's Investment Committee. All assets are externally managed through a combination of active and passive strategies. Managers may only invest in the asset classes for which they have been appointed. The Investment Committee is responsible for setting the policy that provides the framework for management of the plan assets. The Investment Committee has set the minimum and maximum permitted values for each asset class in the Company's pension plan master trust for the year ended December 31, 2018 , as follows: Range U.S. equities 15 - 36% International equities 10 - 29% Fixed income securities 25 - 50% Alternative investments 10 - 25% The general objectives of the Company's pension asset strategy are to earn a rate of return over time to satisfy the benefit obligations of the plans, meet minimum ERISA funding requirements, and maintain sufficient liquidity to pay benefits and address other cash requirements within the master trust. Specific investment objectives include reducing the volatility of pension assets relative to benefit obligations, achieving a competitive, total investment return, achieving diversification between and within asset classes, and managing other risks. Investment objectives for each asset class are determined based on specific risks and investment opportunities identified. Decisions regarding investment policies and asset allocation are made with the understanding of the historical and prospective return and risk characteristics of various asset classes, the effect of asset allocations on funded status, future Company contributions, and projected expenditures, including benefits. The Company updates its asset allocations periodically. The Company uses various analytics to determine the optimal asset mix and considers plan obligation characteristics, duration, liquidity characteristics, funding requirements, expected rates of return, regular rebalancing, and the distribution of returns. Actual allocations to each asset class could vary from target allocations due to periodic investment strategy changes, short-term market value fluctuations, the length of time it takes to fully implement investment allocation positions, such as real estate and other alternative investments, and the timing of benefit payments and Company contributions. Taking into account the asset allocation ranges, the Company determines the specific allocation of the master trust's investments within various asset classes. The master trust utilizes select investment strategies, which are executed through separate account or fund structures with external investment managers who demonstrate experience and expertise in the appropriate asset classes and styles. The selection of investment managers is done with careful evaluation of all aspects of performance and risk, demonstrated fiduciary responsibility, investment management experience, and a review of the investment managers' policies and processes. Investment performance is monitored frequently against appropriate benchmarks and tracked to compliance guidelines with the assistance of third party consultants and performance evaluation tools and metrics. Plan assets are stated at fair value. The Company employs a variety of pricing sources to estimate the fair value of its pension plan assets, including independent pricing vendors, dealer or counterparty-supplied valuations, third-party appraisals, and appraisals prepared by the Company's investment managers or other experts. Investments in equity securities, common and preferred, are valued at the last reported sales price when an active market exists. Securities for which official or last trade pricing on an active exchange is available are classified as Level 1. If closing prices are not available, securities are valued at the last trade price, if deemed reasonable, or a broker's quote in a non-active market, and are typically categorized as Level 2. Investments in fixed-income securities are generally valued by independent pricing services or dealers who make markets in such securities. Pricing methods are based upon market transactions for comparable securities and various relationships between securities that are generally recognized by institutional traders, and fixed-income securities typically are categorized as Level 2. Investments in collective trust funds and commingled funds that use Net Asset Values (“NAV”) are valued based on the redemption price of units owned by the master trust, which is based on the current fair values of the funds’ underlying assets, as reported by the investment manager. Investments in hedge funds generally do not have readily available market quotations and are estimated at fair value, which primarily utilizes NAV or the equivalent, as a practical expedient, as reported by the investment manager. Hedge funds usually have restrictions on redemptions that might affect the ability to sell the investment at NAV in the short term. Real estate funds are typically valued through updated independent third-party appraisals, which are adjusted for changes in cash flows, market conditions, property performance, and leasing status. Since real estate funds do not have readily available market quotations, they are generally valued at NAV or its equivalent, as a practical expedient, as reported by the asset manager. Redemptions from real estate funds are also subject to various restrictions. Private partnership interests include debt and equity investments. These investments are valued based on NAVs or their equivalents, adjusted for capital calls and distributions, reported by the respective general partners. The terms of the partnerships range from seven to ten or more years, and investors do not have the option to redeem their interests in these partnerships. As of December 31, 2018 , unfunded commitments to private partnerships were $132 million . Management reviews independently appraised values, audited financial statements, and additional pricing information to evaluate the net asset values. For the very limited group of investments for which market quotations are not readily available or for which the above valuation procedures are deemed not to reflect fair value, additional information is obtained from the investment manager and evaluated internally to determine whether any adjustments are required to reflect fair value. The Company might be unable to quickly liquidate some assets at amounts close or equal to fair value in order to meet the plans' liquidity requirements or respond to specific events, such as the creditworthiness of any particular issuer or counterparty. Illiquid assets are generally long-term investments that complement the long-term nature of the Company's pension obligations and are generally not used to fund benefit payments in the short term. Management monitors liquidity risk on an ongoing basis and has procedures designed to maintain adequate liquidity for plan requirements. The master trust has considerable investments in fixed income securities for which changes in the relevant interest rate of a particular instrument might result in the inability to secure similar returns upon the maturity or sale. Changes in prevailing interest rates might result in an increase or decrease in fair value of the instrument. Investment managers are permitted to use interest rate swaps and other financial derivatives to manage interest rate and credit risks. Counterparty risk is the risk that a counterparty to a financial instrument held by the master trust will default on its commitment. Counterparty risk is generally related to over-the-counter derivative instruments used to manage risk exposure to interest rates on long-term debt securities. Certain agreements with counterparties employ set-off agreements, collateral support arrangements, and other risk mitigation practices designed to reduce the net credit risk exposure in the event of a counterparty default. The Company has credit policies and processes, which manage concentrations of risk by seeking to undertake transactions with large well-capitalized counterparties and by monitoring the creditworthiness of these counterparties. Certain investments that are measured at fair value using NAV per share (or its equivalent) as a practical expedient are not required to be categorized in the fair value hierarchy table. The total fair value of these investments is included in the table below to permit reconciliation of the fair value hierarchy to amounts presented in the funded status table above. December 31, 2018 ($ in millions) Total Level 1 Level 2 Level 3 Plan assets subject to leveling U.S. and international equities $ 1,174 $ 1,174 $ — $ — Government and agency debt securities 433 — 433 — Corporate and other debt securities 1,265 — 1,265 — Group annuity contract 3 — 3 — Cash and cash equivalents, net — — — — Net plan assets subject to leveling $ 2,875 $ 1,174 $ 1,701 $ — Plan assets not subject to leveling U.S. and international equities (a) 1,910 Corporate and other debt securities 193 Real estate investments 302 Private partnerships 48 Hedge funds 287 Cash and cash equivalents, net (b) 111 Total plan assets not subject to leveling 2,851 Net plan assets $ 5,726 (a) U.S. and international equity securities include investments in small, medium, and large capitalization stocks of public companies held in commingled trust funds. (b) Cash and cash equivalents are liquid short-term investment funds and include net receivables and payables of the trust. These funds are available for immediate use to fund daily operations, execute investment policies, and serve as a temporary investment vehicle. December 31, 2017 ($ in millions) Total Level 1 Level 2 Level 3 Plan assets subject to leveling U.S. and international equities $ 1,270 $ 1,270 $ — $ — Government and agency debt securities 409 — 409 — Corporate and other debt securities 1,287 — 1,287 — Group annuity contract 3 — 3 — Cash and cash equivalents, net — — — — Net plan assets subject to leveling $ 2,969 $ 1,270 $ 1,699 $ — Plan assets not subject to leveling U.S. and international equities (a) 2,012 Corporate and other debt securities 165 Real estate investments 279 Private partnerships 16 Hedge funds 281 Cash and cash equivalents, net (b) 115 Total plan assets not subject to leveling 2,868 Net plan assets $ 5,837 (a) U.S. and international equity securities include investments in small, medium, and large capitalization stocks of public companies held in commingled trust funds. (b) Cash and cash equivalents are liquid short-term investment funds and include net receivables and payables of the trust. These funds are available for immediate use to fund daily operations, execute investment policies, and serve as a temporary investment vehicle. The master trust limits the use of derivatives through direct or separate account investments, such that the derivatives used are liquid and able to be readily valued in the market. Derivative usage in separate account structures is primarily for gaining market exposure in an unlevered manner or hedging investment risks. The fair market value of the pension master trust's derivatives through direct or separate account investments resulted in a net asset of approximately $4 million and a net liability of $1 million as of December 31, 2018 and 2017 , respectively. There was no activity attributable to Level 3 retirement plan assets during the years ended December 31, 2018 and 2017 .

Stock Compensation Plans

Stock Compensation Plans	12 Months Ended
	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Compensation Plans	STOCK COMPENSATION PLANS As of December 31, 2018 , HII had stock-based compensation awards outstanding under the following plans: the Huntington Ingalls Industries, Inc. 2011 Long-Term Incentive Stock Plan (the "2011 Plan") and the Huntington Ingalls Industries, Inc. 2012 Long-Term Incentive Stock Plan (the "2012 Plan"). Stock Compensation Plans On March 23, 2012, the Company's board of directors adopted the 2012 Plan, subject to stockholder approval, and the Company's stockholders approved the 2012 Plan on May 2, 2012. Award grants made on or after May 2, 2012, were made under the 2012 Plan. Award grants made prior to May 2, 2012, were made under the 2011 Plan. No future grants will be made under the 2011 Plan. The 2012 Plan permits awards of stock options, stock appreciation rights, and other stock awards. Each stock option grant is made with an exercise price of not less than 100% of the closing price of HII's common stock on the date of grant. Stock awards, in the form of RPSRs, restricted stock rights ("RSRs"), and stock rights, are granted to key employees and members of the board of directors without payment to the Company. The 2012 Plan authorized (i) 3.4 million new shares; plus (ii) any shares subject to outstanding awards under the 2011 Plan that were subsequently forfeited to the Company; plus (iii) any shares subject to outstanding awards under the 2011 Plan that were subsequently exchanged by the participant as full or partial payment to the Company in connection with any such award or exchanged by a participant or withheld by the Company to satisfy the tax withholding obligations related to any such award. As of December 31, 2018 , the remaining aggregate number of shares of the Company's common stock authorized for issuance under the 2012 Plan was 4.0 million . The 2011 Plan permitted the awards of stock options and other stock awards. Each stock option grant was made with an exercise price of not less than 100% of the closing price of HII's common stock on the date of grant, with the exception of stock options issued at the time of the spin-off in exchange for Northrop Grumman stock options. Stock awards, in the form of stock rights, were granted to members of the board of directors without payment to the Company. Stock Awards Stock awards include RPSRs, RSRs, and stock rights. The fair value of stock awards is determined based on the closing market price of the Company's common stock on the grant date. Compensation expense for stock awards is measured based on the grant date fair value and recognized over the vesting period, generally three years . For purposes of measuring compensation expense, the amount of shares ultimately expected to vest is estimated at each reporting date based on management's expectations regarding the relevant service or performance criteria. The Company issued the following stock awards in the years ended December 31, 2018 , 2017 , and 2016 : Restricted Performance Stock Rights - For the year ended December 31, 2018 , the Company granted approximately 0.1 million RPSRs at a weighted average share price of $261.88 . These rights are subject to cliff vesting on December 31, 2020. For the year ended December 31, 2017 , the Company granted approximately 0.1 million RPSRs at a weighted average share price of $218.54 . These rights are subject to cliff vesting on December 31, 2019. For the year ended December 31, 2016 , the Company granted approximately 0.2 million RPSRs at a weighted average share price of $134.53 . These rights were fully vested as of December 31, 2018. All of the RPSRs are subject to the achievement of performance-based targets at the end of the respective vesting periods and will ultimately vest between 0% and 200% of grant date value. Restricted Stock Rights - Retention stock awards are granted to key employees primarily to ensure business continuity. In 2018 , the Company granted approximately 2,900 RSRs at a weighted average share price of $225.68 , with cliff vesting two to three years from the grant date. In 2017 , the Company granted approximately 3,100 RSRs at a weighted average share price of $188.13 , with cliff vesting two years from the grant date. As of December 31, 2018 , approximately 5,100 of these RSRs were outstanding. For the year ended December 31, 2018 , 0.2 million stock awards vested, of which approximately 0.1 million were transferred to the Company from employees in satisfaction of minimum tax withholding obligations. For the year ended December 31, 2017 , 0.4 million stock awards vested, of which approximately 0.2 million were transferred to the Company from employees in satisfaction of minimum tax withholding obligations. For the year ended December 31, 2016 , 0.8 million stock awards vested, of which approximately 0.3 million were transferred to the Company from employees in satisfaction of minimum tax withholding obligations. Stock Rights and Stock Issuances - The Company granted stock rights to its non-employee directors on a quarterly basis in 2018 , with each grant less than 10,000 shares. All stock rights granted to non-employee directors are fully vested on the grant date. If a non-employee director has met certain stock ownership guidelines, the non-employee director may elect under the terms of the Directors’ Compensation Policy and Board Deferred Compensation Policy to receive their annual equity award for the following calendar year in the form of either shares of the Company’s common stock or stock units that are payable in the fifth calendar year after the year in which the annual equity award is earned, or, if earlier, upon termination of the director’s board service. Non-employee directors may also elect to receive their annual cash retainers in the form of stock units that become payable upon termination of the director’s board service. Non-employee directors who elect to receive their annual cash retainers in the form of stock units and have met their stock ownership guidelines may elect under the terms of the Directors’ Compensation Policy and Board Deferred Compensation Policy to receive stock units for the following calendar year that are payable in the fifth calendar year after the year in which the stock units are earned, or, if earlier, upon termination of the director’s board service. The stock award activity for the years ended December 31, 2018 , 2017 , and 2016 , was as follows: Stock Awards (in thousands) Weighted-Average Grant Date Fair Value Weighted Average Remaining Contractual Term Outstanding as of December 31, 2015 891 $ 75.73 0.6 years Granted 169 134.78 Adjustment due to performance 326 46.75 Vested (783 ) 46.75 Forfeited (25 ) 127.45 Outstanding as of December 31, 2016 578 113.95 0.8 years Granted 109 217.02 Adjustment due to performance 163 97.00 Vested (387 ) 97.00 Forfeited (14 ) 154.75 Outstanding as of December 31, 2017 449 147.13 0.8 years Granted 99 259.62 Adjustment due to performance 98 142.85 Vested (235 ) 142.85 Forfeited (12 ) 218.50 Outstanding as of December 31, 2018 399 $ 174.07 0.7 years Vested awards include stock awards that fully vested during the year based on the level of achievement of the relevant performance goals. The performance goals for outstanding RPSRs granted in 2018 , 2017 , and 2016 are based on two metrics as defined in the grant agreements: earnings before interest, taxes, depreciation, amortization, and pension, weighted at 50% , and pension-adjusted return on invested capital, weighted at 50% . Stock Options Effect of the Spin-Off - Prior to the spin-off from Northrop Grumman, HII's current and former employees received stock options under Northrop Grumman's stock-based award plans (the "Northrop Grumman Plan"). As of the date of the spin-off, the stock options under the Northrop Grumman Plan were converted to stock options under the 2011 Plan. The conversion was effected so that the outstanding stock options held by the Company's current and former employees on the distribution date were adjusted to reflect the value of the distribution, such that the intrinsic value of the stock options was not diluted at the time of, and due to, the separation. This was achieved using the conversion rate included in the spin-off agreement. Unless otherwise stated, share amounts and share prices detailed below were retroactively adjusted to reflect the impact of the conversion. The Company measured the fair value of the stock options immediately before and after the conversion, and there was no incremental compensation expense associated with the conversion. The following is a description of the Northrop Grumman Plan stock options, which were converted into stock options under the 2011 Plan. Converted Stock Options - As of the date of the spin-off, outstanding stock options held by HII's current and former employees under the Northrop Grumman Plan were converted to stock options of HII under the 2011 Plan. Based on the conversion factor of 1.65 , included in the spin-off agreement, approximately 1.0 million stock options under the Northrop Grumman Plan were converted into approximately 1.6 million stock options under the 2011 Plan, approximately 1.4 million of which were fully vested at the time of conversion. Outstanding stock options granted prior to 2008 generally vested in 25% increments over four years from the grant date and expired ten years after the grant date. Stock options granted in 2008 and later vested in 33% increments over three years from the grant date and expired seven years after the grant date. The cumulative intrinsic value of the stock options at conversion was maintained in the conversion, and totaled $15 million at March 31, 2011. Compensation expense for the outstanding converted stock options was determined at the time of grant by Northrop Grumman. No stock options were granted during the years ended December 31, 2018 , 2017 , and 2016 . The fair value of the stock options was expensed on a straight-line basis over the vesting period of the options. The fair value of each of the stock options was estimated on the date of grant using a Black-Scholes option pricing model. The stock option activity for the years ended December 31, 2018 , 2017 , and 2016 , was as follows: Shares Under Option (in thousands) Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value ($ in millions) Outstanding as of December 31, 2015 533 $ 33.90 0.6 years $ 50 Exercised (271 ) 30.20 Outstanding as of December 31, 2016 262 37.73 0.1 years 38 Exercised (262 ) 37.73 Outstanding as of December 31, 2017 — — — Outstanding as of December 31, 2018 — $ — $ — Vested as of December 31, 2018 — $ — $ — The intrinsic value of stock options exercised during the years ended December 31, 2017 and 2016, was $43 million and $26 million , respectively. Intrinsic value was measured using the fair market value at the date of exercise for stock options exercised or at period end for outstanding stock options, less the applicable exercise price. The Company issued new shares to satisfy exercised stock options. Compensation Expense The Company recorded $36 million , $34 million , and $36 million of expense related to stock awards for the years ended December 31, 2018 , 2017 , and 2016 , respectively. The Company recorded $8 million , $9 million (net of impact of reduction in statutory federal corporate income tax rate), and $14 million as tax benefits related to stock awards and stock options for the years ended December 31, 2018 , 2017 , and 2016 , respectively. The Company recognized tax benefits for the years ended December 31, 2018 , 2017 , and 2016 , of $16 million , $28 million , and $39 million , respectively, from the issuance of stock in settlement of stock awards, and $17 million and $10 million for the years ended December 31, 2017 and 2016 , respectively, from the exercise of stock options. All outstanding stock options were exercised as of December 31, 2017. Accordingly, there were no tax benefits associated with the exercise of stock options in 2018. Unrecognized Compensation Expense As of December 31, 2018 , the Company had less than $1 million of unrecognized compensation expense associated with RSRs granted in 2018 and 2017, which will be recognized over a weighted average period of 1.3 years , and $25 million of unrecognized expense associated with RPSRs granted in 2018 and 2017 , which will be recognized over a weighted average period of 0.8 years . As of December 31, 2018 , the Company had no unrecognized compensation expense related to stock options.

Unaudited Selected Quarterly Da

Unaudited Selected Quarterly Data	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Unaudited Selected Quarterly Data	UNAUDITED SELECTED QUARTERLY DATA Unaudited quarterly financial results for the years ended December 31, 2018 and 2017 , are set forth in the following tables: Year Ended December 31, 2018 ($ in millions, except per share amounts) 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Sales and service revenues $ 1,874 $ 2,020 $ 2,083 $ 2,199 Operating income 191 257 290 213 Earnings before income taxes 195 262 295 219 Net earnings 156 239 229 212 Dividends declared per share $ 0.72 $ 0.72 $ 0.72 $ 0.86 Basic earnings per share $ 3.48 $ 5.41 $ 5.29 $ 4.96 Diluted earnings per share $ 3.48 $ 5.40 $ 5.29 $ 4.94 Year Ended December 31, 2017 ($ in millions, except per share amounts) 1st Qtr 2nd Qtr (1) 3rd Qtr 4th Qtr (2) Sales and service revenues $ 1,724 $ 1,858 $ 1,863 $ 1,996 Operating income 168 241 241 231 Earnings before income taxes 147 218 220 187 Net earnings 119 147 149 64 Dividends declared per share $ 0.60 $ 0.60 $ 0.60 $ 0.72 Basic earnings per share $ 2.57 $ 3.22 $ 3.28 $ 1.41 Diluted earnings per share $ 2.56 $ 3.21 $ 3.27 $ 1.41 (1) In the second quarter of 2017, the Company recorded a $30 million favorable cumulative adjustment on a contract at the Ingalls segment. (2) In the fourth quarter of 2017, the Tax Act resulted in an increase of $56 million to the Company's income tax expense.

Subsidiary Guarantors

Subsidiary Guarantors	12 Months Ended
	Dec. 31, 2018
Subsidiary Guarantors [Abstract]
Guarantor Subsidiaries [Text Block]	SUBSIDIARY GUARANTORS As described in Note 14, the Company issued senior notes through the consolidating parent company, HII. Performance of the Company's obligations under its senior notes outstanding as of December 31, 2018 , including any repurchase obligations resulting from a change of control, is fully and unconditionally guaranteed, jointly and severally, on an unsecured basis, by each of HII's existing and future material domestic subsidiaries ("Subsidiary Guarantors"). The Subsidiary Guarantors are 100% owned by HII. Under SEC Regulation S-X Rule 3-10, each HII subsidiary that did not provide a guarantee ("Non-Guarantors") is minor and HII, as the parent company issuer, did not have independent assets or operations. There are no significant restrictions on the ability of the parent company and the Subsidiary Guarantors to obtain funds from their respective subsidiaries by dividend or loan, except those imposed by applicable law.

Subsequent Event

Subsequent Event	12 Months Ended
	Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events [Text Block]	SUBSEQUENT EVENT In January 2019, the Company entered into an agreement to acquire Fulcrum IT Services, LLC, an information technology and government consulting company. Completion of the transaction, which is expected to occur in the first quarter of 2019, is subject to certain required regulatory approvals and the satisfaction of other customary closing conditions.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation - The consolidated financial statements of HII and its subsidiaries have been prepared in conformity with accounting principles generally accepted in the United States of America ("GAAP") and the instructions to Form 10-K promulgated by the Securities and Exchange Commission ("SEC"). All intercompany transactions and balances are eliminated in consolidation. For classification of current assets and liabilities related to its long-term production contracts, the Company uses the duration of these contracts as its operating cycle, which is generally longer than one year. Additionally, certain prior year amounts have been reclassified to conform to the current year presentation. See Note 3: Accounting Standards Updates.
Accounting Estimates	Accounting Estimates - The preparation of the Company's consolidated financial statements requires management to make estimates and judgments that affect the reported amounts of assets and liabilities and the disclosure of contingencies at the date of the financial statements, as well as the reported amounts of revenues and expenses during the reporting period. Estimates have been prepared on the basis of the most current and best available information, and actual results could differ materially from those estimates. In August 2011, the Budget Control Act established limits on U.S. Government discretionary spending, and provided for potential sequestration cuts to defense spending and non-defense discretionary spending. The Bipartisan Budget Act of 2018 (the "BBA 2018") provided sequestration relief for fiscal years 2018 and 2019. Sequestration remains in effect for fiscal years 2020 and 2021 and could result in significant decreases in DoD spending that could negatively impact the Company's consolidated financial position, results of operations, or cash flows, as well as its estimated recovery of goodwill and other long-lived assets.
Revenue Recognition	Revenue Recognition - Effective January 1, 2018, the Company adopted the requirements of Accounting Standards Update ("ASU") 2014-09, Revenue from Contracts with Customers (Topic 606), and related amendments . Prior to January 1, 2018, the Company recognized revenue in accordance with Accounting Standards Codification Topic 605-35 Construction-Type and Production-Type Contracts utilizing the cost-to-cost measure of the percentage-of-completion method of accounting, primarily based upon total costs incurred, with incentive fees included in sales when the amounts could be reasonably determined and estimated . Amounts representing change orders, claims, requests for equitable adjustment, or limitations of funding were included in sales only when they could be reliably estimated and realization was probable. For services contracts not associated with the design, development, manufacture, or modification of complex equipment, revenues were recognized upon delivery or as services are rendered once persuasive evidence of an arrangement exists, the price is fixed or determinable, and collectability is reasonably assured. Costs related to these contracts were expensed as incurred. For additional information on the new standard and the impact to the Company's results of operations, refer to Note 3: Accounting Standards Updates. Most of the Company's revenues are derived from long-term contracts for the production of goods and services provided to its U.S. Government customers. The Company generally recognizes revenues on contracts with U.S. Government customers over time using a cost-to-cost measure of progress. The use of the cost-to-cost method to measure performance progress over time is supported by clauses in the related contracts that allow the customer to unilaterally terminate the contract for convenience, pay the Company for costs incurred plus a reasonable profit, and take control of any work in process. The Company utilizes the cost-to-cost method to measure performance progress, because it best reflects the continuous transfer of control over the related goods and services to the customer as the Company satisfies its performance obligations. When the customer is not a U.S. Government entity, the Company may recognize revenue over time or at a point in time when control transfers upon delivery, depending upon the facts and circumstances of the related arrangement. When the Company determines that revenue should be recognized over time, the Company utilizes a measure of progress that best depicts the transfer of control of the relevant goods and services to the customer. Generally, the terms and conditions of the contracts result in a transfer of control over the related goods and services as the Company satisfies its performance obligations. Accordingly, the Company recognizes revenue over time using the cost-to-cost method to measure performance progress. The Company may, however, utilize a measure of progress other than cost-to-cost, such as a labor-based measure of progress, if the terms and conditions of the arrangement require such accounting. When using the cost-to-cost method to measure performance progress, certain contracts may include costs that are not representative of performance progress, such as large upfront purchases of uninstalled materials, unexpected waste, or inefficiencies. In these cases, the Company adjusts its measure of progress to exclude such costs, with the goal of better reflecting the transfer of control over the related goods or services to the customer and recognizing revenue only to the extent of the costs incurred that reflect the Company's performance under the contract. In addition, for time and material arrangements, the Company often utilizes the practical expedient allowing the recognition of revenue in the amount the Company invoices, which corresponds with the value provided to the customer and to which the Company is entitled to payment for performance to date. A performance obligation is a promise to transfer a distinct good or service to the customer and is the unit of account for which revenue is recognized. To determine the proper revenue recognition method, consideration is given to whether two or more contracts should be combined and accounted for as one contract and whether a single contract consists of more than one performance obligation. For contracts with multiple performance obligations, the contract transaction price is allocated to each performance obligation using an estimate of the standalone selling price based upon expected cost plus a margin at contract inception, which is generally the price disclosed in the contract. Contracts are often modified to account for changes in contract specifications and requirements. In the majority of circumstances, modifications do not result in additional performance obligations that are distinct from the existing performance obligations in the contract, and the effects of the modifications are recognized as an adjustment to revenue on a cumulative catch-up basis. Alternatively, in instances in which the performance obligations in the modifications are deemed distinct, contract modifications are accounted for prospectively. The amount of revenue recognized as the Company satisfies performance obligations associated with contracts with customers is based upon the determination of transaction price. Transaction price reflects the amount of consideration to which the Company expects to be entitled for performance under the terms and conditions of the relevant contract and may reflect fixed and variable components, including shareline incentive fees whereby the value of the contract is variable based upon the amount of costs incurred, as well as other incentive fees based upon achievement of contractual schedule commitments or other specified criteria in the contract. Shareline incentive fees are determined based upon the formula under the relevant contract using the Company’s estimated cost to complete for each period. The Company generally utilizes a most likely amount approach to estimate variable consideration. In all such instances, the estimated revenues represent those amounts for which the Company believes a significant reversal of revenue is not probable.
Contract Estimates	Contract Estimates - In estimating contract costs, the Company utilizes a profit-booking rate based upon performance expectations that takes into consideration a number of assumptions and estimates regarding risks related to technical requirements, feasibility, schedule, and contract costs. Management performs periodic reviews of the contracts to evaluate the underlying risks, which may increase the profit-booking rate as the Company is able to mitigate and retire such risks. Conversely, if the Company is not able to retire these risks, cost estimates may increase, resulting in a lower profit-booking rate. The cost estimation process requires significant judgment and is based upon the professional knowledge and experience of the Company’s engineers, program managers, and financial professionals. Factors considered in estimating the work to be completed and ultimate contract recovery include the availability, productivity, and cost of labor, the nature and complexity of the work to be performed, the effect of change orders, the availability of materials, the effect of any performance delays, the availability and timing of funding from the customer, and the recoverability of any claims included in the estimates to complete. Changes in estimates of sales, costs, and profits on a performance obligation are recognized using the cumulative catch-up method of accounting, which recognizes in the current period the cumulative effect of the changes in current and prior periods. A significant change in an estimate on one or more contracts in a period could have a material effect on the Company's consolidated financial position or results of operations for that period. When estimates of total costs to be incurred exceed estimates of total revenue to be earned on a performance obligation related to a complex, construction-type contract, a provision for the entire loss on the performance obligation is recognized in the period the loss is determined.
Accounts Receivable	Accounts Receivable - Accounts receivable include amounts related to any unconditional Company right to receive consideration and are presented as receivables in the condensed consolidated statement of financial position, separate from other contract balances. Accounts receivable are comprised of amounts billed and currently due from customers. The Company reports accounts receivable net of an allowance for doubtful accounts. Because the Company's accounts receivable are primarily with the U.S. Government or with companies acting as a contractor to the U.S. Government, the Company does not have material exposure to accounts receivable credit risk.
Contract Assets	Contract Assets - Contract assets primarily relate to the Company’s rights to consideration for work completed but not billed as of the reporting date when the right to payment is not just subject to the passage of time, including retention amounts. Contract assets are classified as current assets and, in accordance with industry practice, include amounts that may be billed and collected beyond one year due to the long term nature of many of the Company's contracts. Contract assets are transferred to accounts receivable when the right to consideration becomes unconditional.
Contract Liabilities	Contract Liabilities - Contract liabilities are comprised of advance payments, billings in excess of revenues, and deferred revenue amounts. Such advances are generally not considered a significant financing component, because they are utilized to pay for contract costs within a one year period. Contract liability amounts are recognized as revenue once the requisite performance progress has occurred.
Inventoried Costs	Inventoried Costs - Inventoried costs primarily relate to company owned raw materials, which are stated at the lower of cost or net realizable value, generally using the average cost method, and costs capitalized pursuant to applicable provisions of the Federal Acquisition Regulation ("FAR") and U.S. Cost Accounting Standards ("CAS"). Under the Company's U.S. Government contracts, the customer asserts title to, or a security interest in, inventories related to such contracts as a result of contract advances, performance-based payments, and progress payments. In accordance with industry practice, inventoried costs are classified as current assets and include amounts related to contracts having production cycles longer than one year.
Warranty Costs	Warranty Costs - Certain of the Company’s contracts contain assurance-type warranty provisions, which generally promise that the service or vessel will comply with agreed upon specifications. In such instances, the Company accrues the estimated loss by a charge to income in the relevant period. In limited circumstances, the Company's complex construction type contracts may provide the customer with an option to purchase a warranty or provide an extended assurance service coupled with the primary assurance warranty. In such cases, the Company accounts for the warranty as a separate performance obligation to the extent it is material within the context of the contract. Warranty liabilities are reported within other current liabilities and are not material.
Government Grants	Government Grants - The Company recognizes incentive grants, inclusive of transfers of depreciable assets, from federal, state, and local governments at fair value upon compliance with the conditions of their receipt and reasonable assurance that the grants will be received or the depreciable assets will be transferred. Grants in recognition of specific expenses are recognized in the same period as an offset to those related expenses. Grants related to depreciable assets are recognized over the periods and in the proportions in which depreciation expense on those assets is recognized. For the years ended December 31, 2018 and 2017 , the Company recognized cash grant benefits of $61 million and $21 million , respectively, in other long-term liabilities in the consolidated statements of financial position. For the year ended December 31, 2016, the Company recognized grant benefits of approximately $30 million in depreciable assets and approximately $15 million in other income and gains within the consolidated statements of operations and comprehensive income, and recognized approximately $15 million in grant benefits in other long-term liabilities in the consolidated statements of financial position.
General and Administrative Expenses	General and Administrative Expenses - In accordance with industry practice and regulations that govern the cost accounting requirements for government contracts, most general corporate expenses incurred at both the segment and corporate locations are allowable and allocable costs on government contracts. These costs are allocated to contracts in progress on a systematic basis, and contract performance factors include this as an element of cost. General and administrative expenses also include certain other costs that do not affect segment operating income, primarily non-current state income taxes. Non-current state income taxes include deferred state income taxes, which reflect the change in deferred state tax assets and liabilities, and the tax expense or benefit associated with changes in state uncertain tax positions in the relevant period.
Research and Development	Research and Development - Company-sponsored research and development activities primarily include independent research and development ("IR&D") related to experimentation, design, development, and test activities for government programs. IR&D expenses are included in general and administrative expenses and are generally allocable to government contracts. Company-sponsored IR&D expenses totaled $25 million , $17 million , and $19 million for the years ended December 31, 2018 , 2017 , and 2016 , respectively. Expenses for research and development sponsored by the customer are charged directly to the related contracts.
Environmental Costs	Environmental Costs - Environmental liabilities are accrued when the Company determines remediation costs are probable and such costs are reasonably estimable. When only a range of costs is established and no amount within the range is more probable than another, the minimum amount in the range is accrued. Environmental liabilities are recorded on an undiscounted basis and are not material. Environmental expenditures are expensed or capitalized as appropriate. Capitalized expenditures, if any, relate to long-lived improvements in currently operating facilities. The Company does not record insurance recoveries before collection is probable. As of December 31, 2018 and 2017 , the Company did not have any accrued receivables related to insurance reimbursements or recoveries for environmental matters.
Fair Value of Financial Instruments	Fair Value of Financial Instruments - The accounting standard for fair value measurements provides a framework for measuring fair value and requires expanded disclosures regarding fair value measurements. 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 on the measurement date. The accounting standard provides a fair value hierarchy, which requires an entity to maximize the use of observable inputs, where available. The three levels of inputs consist of: Level 1: Quoted prices in active markets for identical assets and liabilities. Level 2: Observable inputs, other than Level 1 prices, such as: quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or that the Company corroborates with observable market data for substantially the full term of the related assets or liabilities. Level 3: Unobservable inputs supported by little or no market activity that are significant to the fair value of the assets and liabilities. Except for the Company's long-term debt, the carrying amounts of the Company's financial instruments recorded at historical cost approximate fair value due to the short-term nature of the instruments and low credit risk associated with the respective counterparties. The Company maintains multiple grantor trusts to fund certain non-qualified pension plans. These trusts were valued at $109 million and $94 million as of December 31, 2018 and 2017 , respectively, and are presented within miscellaneous other assets within the consolidated statements of financial position. These trusts consist primarily of investments in marketable securities, which are held at fair value within Level 1 of the fair value hierarchy.
Foreign Currency Translation	Foreign Currency Translation - The Company's international subsidiaries that do not have the U.S. dollar as their functional currency translate assets and liabilities at current rates of exchange in effect at the balance sheet date. Revenues and expenses from these international subsidiaries are translated using the monthly average exchange rates in effect for the periods in which the items occur. The cumulative foreign currency translation gains and losses are included as a component of accumulated other comprehensive loss in stockholders’ equity. Gains and losses from foreign currency transactions are included in other income (expense) in the consolidated statements of operations and comprehensive income. Such amounts are not material.
Asset Retirement Obligations	Asset Retirement Obligations - Environmental remediation and/or asset decommissioning may be required when the Company ceases to utilize certain facilities. The Company records, within other current liabilities or other long-term liabilities as appropriate, all known asset retirement obligations for which the liability's fair value can be reasonably estimated, including certain asbestos removal, asset decommissioning, and lease restoration obligations. Asset retirement obligations for which the liability's fair value can be reasonably estimated were immaterial as of December 31, 2018 and 2017 . The Company also has known conditional asset retirement obligations related to assets currently in use, including certain asbestos remediation and asset decommissioning activities to be performed in the future, that were not reasonably estimable as of December 31, 2018 , due to insufficient information about the timing and method of settlement of the obligation. Accordingly, the fair value of these obligations has not been recorded in the consolidated financial statements. A liability for these obligations is recorded in the period in which sufficient information regarding timing and method of settlement becomes available to make a reasonable estimate of the liability's fair value. In addition, there may be conditional environmental asset retirement obligations that the Company has not yet discovered.
Income Taxes	Income Taxes - Income tax expense and other related information are based on the prevailing statutory rates for U.S. federal income taxes and the composite state income tax rate for the Company for each period presented. Non-current state income taxes include deferred state income taxes, which reflect the change in deferred state tax assets and liabilities, and the tax expense or benefit associated with changes in state uncertain tax positions in the relevant period. These amounts are recorded within operating income, while the current period state income tax expense, which is generally allowable and allocable to contracts, is charged to contract costs and included in cost of sales and service revenues in segment operating income. Deferred income taxes are recorded when revenues and expenses are recognized in different periods for financial statement purposes and for tax return purposes. Deferred tax asset or liability account balances are calculated at the balance sheet date using current tax laws and rates expected to be in effect when the deferred tax items reverse in future periods. As a result of the reduction in the corporate income tax rate from 35% to 21% effective January 1, 2018, under the Tax Cuts and Jobs Act (the "Tax Act"), the Company revalued its net deferred tax assets. See Note 13: Income Taxes in Item 8. The Company recognizes deferred tax assets to the extent it believes these assets are more likely than not to be realized. In making such a determination, the Company considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. Based on the Company's evaluation of these deferred tax assets, valuation allowances of $12 million were deemed necessary as of each of December 31, 2018 and 2017 . Uncertain tax positions meeting the more-likely-than-not recognition threshold, based on the merits of the position, are recognized in the financial statements. The Company recognizes the amount of tax benefit that is greater than 50% likely to be realized upon ultimate settlement with the related tax authority. If a tax position does not meet the minimum statutory threshold to avoid payment of penalties, the Company recognizes an expense for the amount of the penalty in the period the tax position is claimed or expected to be claimed in its tax return. Penalties and accrued interest related to uncertain tax positions are recognized as a component of income tax expense. Changes in accruals associated with uncertain tax positions are recorded in earnings in the period in which they are determined.
Cash and Cash Equivalents	Cash and Cash Equivalents - The carrying amounts of cash and cash equivalents approximate fair value due to the short-term nature of these assets, which have original maturity dates of 90 days or less.
Concentration Risk	Concentration Risk - The Company’s assets that are exposed to concentrations of credit risk consist primarily of cash and cash equivalents. The Company places its cash and cash equivalents with reputable financial institutions and limits the amount of credit exposure with any one of them. The Company regularly evaluates the creditworthiness of these financial institutions and minimizes this credit risk by entering into transactions with high-quality counterparties, limiting the exposure to each counterparty, and monitoring the financial condition of its counterparties. In connection with its U.S. Government contracts, the Company is required to procure certain raw materials, components, and parts from supply sources approved by the U.S. Government. Only one supplier may exist for certain components and parts required to manufacture the Company's products.
Property, Plant, and Equipment	Property, Plant, and Equipment - Depreciable properties owned by the Company are recorded at cost and depreciated over the estimated useful lives of individual assets. Major improvements are capitalized while expenditures for maintenance, repairs, and minor improvements are expensed. Costs incurred for computer software developed or purchased for internal use are capitalized and amortized over the expected useful life of the software, not to exceed nine years. Leasehold improvements are amortized over the shorter of their useful lives or the term of the lease. The remaining assets are depreciated using the straight-line method, with the following lives: Years Land improvements 2 - 40 Buildings and improvements 2 - 60 Capitalized software costs 3 - 9 Machinery and other equipment 2 - 45 The Company evaluates the recoverability of its property, plant, and equipment when there are changes in economic circumstances or business objectives that indicate the carrying value may not be recoverable. The Company's evaluations include estimated future cash flows, profitability, and other factors affecting fair value. As these assumptions and estimates may change over time, it may or may not be necessary to record impairment charges.
Leases	Leases - The Company uses its incremental borrowing rate in the assessment of lease classification as capital or operating and defines the initial lease term to include renewal options determined to be reasonably assured. The Company conducts operations primarily under operating leases. Many of the Company's real property lease agreements contain incentives for tenant improvements, rent holidays, or rent escalation clauses. For incentives for tenant improvements, the Company records a deferred rent liability and amortizes the deferred rent over the term of the lease as a reduction to rent expense. For rent holidays and rent escalation clauses during the lease term, the Company records minimum rental expenses on a straight-line basis over the term of the lease. For purposes of recognizing lease incentives, the Company uses the date of initial possession as the commencement date, which is generally the date on which the Company is given the right of access to the space and begins to make improvements in preparation for the intended use.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets - The Company performs impairment tests for goodwill as of November 30 of each year and between annual impairment tests if evidence of potential impairment exists, by comparing the carrying value of net assets to the fair value of the reporting unit. If the fair value is determined to be less than the carrying value, the Company records an impairment charge to the reporting unit. Purchased intangible assets are amortized on a straight-line basis or a method based on the pattern of benefits over their estimated useful lives, and the carrying value of these assets is reviewed for impairment when events indicate that a potential impairment may have occurred.
Equity Method Investments	Equity Method Investments - Investments in which the Company has the ability to exercise significant influence over the investee but does not own a majority interest or otherwise control are accounted for under the equity method of accounting and included in other assets in its consolidated statements of financial position. The Company's equity investments align strategically and are integrated with the Company's operations. Accordingly, the Company's share of the net earnings or losses of the investee is included in operating income. The Company evaluates its equity investments for other than temporary impairment whenever events or changes in business circumstances indicate that the carrying amounts of such investments may not be fully recoverable. If a decline in the value of an equity method investment is determined to be other than temporary, a loss is recorded in earnings in the current period.
Self-Insured Workers' Compensation Plan	Self-Insured Group Medical Insurance - The Company maintains a self-insured group medical insurance plan. The plan is designed to provide a specified level of coverage for employees and their dependents. Estimated liabilities for incurred but not paid claims utilize actuarial methods based on various assumptions, which include, but are not limited to, HII's historical loss experience and projected loss development factors. These liabilities are recorded in other current liabilities and account for less than 5% of the total current liabilities balance. Self-Insured Workers' Compensation Plan - The operations of the Company are subject to federal and state workers' compensation laws. The Company maintains self-insured workers' compensation plans and participates in federally administered second injury workers' compensation funds. The Company estimates the liability for claims and funding requirements on a discounted basis utilizing actuarial methods based on various assumptions, which include, but are not limited to, the Company's historical loss experience and projected loss development factors as compiled in an annual actuarial study. Self-insurance accruals include amounts related to the liability for reported claims and an estimated accrual for claims incurred but not reported. The Company's workers' compensation liability was discounted at 2.89% and 2.35% as of December 31, 2018 and 2017 , respectively. These discount rates were determined using a risk-free rate based on future payment streams. Workers' compensation benefit obligations on an undiscounted basis were $845 million and $925 million as of December 31, 2018 and 2017 , respectively.
Litigation, Commitments, and Contingencies	Litigation, Commitments, and Contingencies - Amounts associated with litigation, commitments, and contingencies are recorded as charges to earnings when management, after taking into consideration the facts and circumstances of each matter, including any settlement offers and projected loss or claim development factors, has determined it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated.
Restructuring	Restructuring - Restructuring related accruals are reviewed and adjusted when circumstances require such a change. Accruals for restructuring activities include estimates primarily related to facility consolidations and closures, asset retirement obligations, long-lived asset write-downs, employment reductions, and contract termination costs. There are no restructuring accruals or activity as of and for the years ended December 31, 2018 , 2017 and 2016 .
Loan Receivable	Loan Receivable - The Company holds a loan receivable in connection with a seller financed transaction involving its previously owned Avondale Shipyard facility. The receivable is carried at amortized cost in the amount of $38 million , net of a $10 million loan discount, which approximates fair value and is recorded in miscellaneous other assets on the consolidated statements of financial position. Interest income is recognized on an accrual basis using the effective yield method. The discount is accreted into income using the effective yield method over the estimated life of the loan receivable.
Retirement Related Benefit Costs	Retirement Related Benefit Costs - The Company accounts for its retirement related benefit plans on the accrual basis. The measurements of obligations, costs, assets, and liabilities require significant judgment. The costs of benefits provided by defined benefit pension plans are recorded in the period participating employees provide service. The costs of benefits provided by other postretirement benefit plans are recorded in the period participating employees attain full eligibility. The discount rate assumption is defined under GAAP as the rate at which a plan's obligation could be effectively settled. The discount rate is established for each of the retirement related benefit plans at its respective measurement date. The expected return on plan assets component of retirement related costs is used to calculate net periodic expense. Unless plan assets and benefit obligations are subject to remeasurement during the year, the expected return on assets is based on the fair value of plan assets at the beginning of the year. The costs of plan amendments that provide benefits already earned by plan participants (prior service costs and credits) are deferred in accumulated other comprehensive loss and amortized over the expected future service period of active participants as of the date of amendment. Actuarial gains and losses arising from differences between assumptions and actual experience or changes in assumptions are deferred in accumulated other comprehensive loss. This unrecognized amount is amortized to the extent it exceeds 10% of the greater of the plan's benefit obligation or plan assets. The amortization period for actuarial gains and losses is the estimated remaining service life of the plan participants. The Company recognizes the funded status of each retirement related benefit plan as an asset or liability in its consolidated statements of financial position. The funded status represents the difference between the plan's benefit obligation and the fair value of the plan's assets. Unrecognized deferred amounts, such as demographic or asset gains or losses and the impacts of plan amendments, are included in accumulated other comprehensive loss and amortized as described above.
Stock Compensation	Stock Compensation - Stock-based compensation value is determined based on the closing market price of the Company's common stock on grant date, and the expense is recognized over the vesting period. At each reporting date, the number of shares is adjusted to equal the number ultimately expected to vest based on the Company's expectations regarding the relevant performance and service criteria.
Related Party Transactions	Related Party Transactions - On March 29, 2011, HII entered into a Separation and Distribution Agreement (the "Separation Agreement") with its former parent company, Northrop Grumman Corporation ("Northrop Grumman"), and Northrop Grumman's subsidiaries (Northrop Grumman Shipbuilding, Inc. and Northrop Grumman Systems Corporation), pursuant to which HII was legally and structurally separated from Northrop Grumman. As of December 31, 2017 , the Company was due $8 million from Northrop Grumman under spin-off related agreements. For the year ended December 31, 2018 , the Company received the $8 million from Northrop Grumman. As of December 31, 2018 and 2017 , the Company had $84 million outstanding under Industrial Revenue Bonds issued by the Mississippi Business Finance Corporation. Prior to the spin-off, repayment of principal and interest was guaranteed by Northrop Grumman Systems Corporation. The guaranty remains in effect, and the Company has agreed to indemnify Northrop Grumman Systems Corporation for any losses related to the guaranty.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Schedule of Depreciable Assets, Straight-Line Method Useful Lives	The remaining assets are depreciated using the straight-line method, with the following lives: Years Land improvements 2 - 40 Buildings and improvements 2 - 60 Capitalized software costs 3 - 9 Machinery and other equipment 2 - 45

Accounting Standards Updates (T

Accounting Standards Updates (Tables)	12 Months Ended
	Dec. 31, 2018
Prospective Adoption of New Accounting Pronouncements [Abstract]
Schedule of Prospective Adoption of New Accounting Pronouncements [Table Text Block]	The following table is a schedule of the impact of adoption of ASU 2017-07 for the years ended December 31, 2017 and 2016. The Company has reclassified the following line items on its previously issued consolidated financial statements to conform to the current year presentation. As Previously Reported As Revised Year Ended December 31 Year Ended December 31 ($ in millions) 2017 2016 2017 2016 Sales and service revenues Product sales $ 5,573 $ 5,631 $ 5,573 $ 5,631 Service revenues 1,868 1,437 1,868 1,437 Sales and service revenues 7,441 7,068 7,441 7,068 Cost of sales and service revenues Cost of product sales 4,444 4,380 4,277 4,237 Cost of service revenues 1,574 1,228 1,536 1,208 Income from operating investments, net 12 6 12 6 Other income and gains — 15 — 15 General and administrative expenses 570 623 759 768 Goodwill impairment — — — — Operating income 865 858 881 876 Other income (expense) Interest expense (94 ) (74 ) (94 ) (74 ) Non-operating retirement expense — — (16 ) (18 ) Other, net 1 — 1 — Earnings before income taxes 772 784 772 784 Federal and foreign income taxes 293 211 293 211 Net earnings $ 479 $ 573 $ 479 $ 573

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2018
Stockholders' Equity Note [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	The changes in accumulated other comprehensive loss by component for the years ended December 31, 2018 , 2017 , and 2016 , were as follows: ($ in millions) Benefit Plans Other Total Balance as of December 31, 2015 $ (843 ) $ (2 ) $ (845 ) Other comprehensive loss before reclassifications (249 ) (1 ) (250 ) Amounts reclassified from accumulated other comprehensive loss Amortization of prior service (credit) 1 (1 ) — (1 ) Amortization of net actuarial loss 1 78 — 78 Tax benefit for items of other comprehensive income 67 — 67 Net current period other comprehensive loss (105 ) (1 ) (106 ) Balance as of December 31, 2016 (948 ) (3 ) (951 ) Other comprehensive income (loss) before reclassifications (34 ) 14 (20 ) Amounts reclassified from accumulated other comprehensive loss Amortization of net actuarial loss 1 93 — 93 Tax expense for items of other comprehensive income (17 ) (5 ) (22 ) Net current period other comprehensive income 42 9 51 Balance as of December 31, 2017 (906 ) 6 (900 ) Other comprehensive loss before reclassifications (312 ) (2 ) (314 ) Amounts reclassified from accumulated other comprehensive loss Amortization of prior service cost 1 2 — 2 Amortization of net actuarial loss 1 78 — 78 Tax expense for items of other comprehensive income 59 — 59 Net current period other comprehensive loss (173 ) (2 ) (175 ) Effect of Accounting Standards Update 2016-01 2 $ — $ (11 ) $ (11 ) Effect of Accounting Standards Update 2018-02 3 $ (204 ) $ 2 $ (202 ) Balance as of December 31, 2018 $ (1,283 ) $ (5 ) $ (1,288 ) 1 These accumulated comprehensive loss components are included in the computation of net periodic benefit cost. See Note 17: Employee Pension and Other Postretirement Benefits. The tax expense associated with amounts reclassified from accumulated other comprehensive loss for the years ended December 31, 2018 , 2017 , and 2016 , was $21 million , $36 million , and $27 million , respectively. 2 The Company adopted ASU 2016-01 as of January 1, 2018. Accordingly, accumulated other comprehensive income of $11 million related to available-for-sale securities, net of $4 million tax expense, was reclassified to retained earnings. 3 The Company adopted ASU 2018-02 as of January 1, 2018. Accordingly, stranded tax effects of $202 million related to the Tax Act were reclassified to retained earnings.

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Basic and Diluted Earnings Per Share	Basic and diluted earnings per common share were calculated as follows: Year Ended December 31 (in millions, except per share amounts) 2018 2017 2016 Net earnings $ 836 $ 479 $ 573 Weighted-average common shares outstanding 43.8 45.7 46.8 Net effect of dilutive stock options and awards — 0.1 0.4 Dilutive weighted-average common shares outstanding 43.8 45.8 47.2 Earnings per share - basic $ 19.09 $ 10.48 $ 12.24 Earnings per share - diluted $ 19.09 $ 10.46 $ 12.14

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Dec. 31, 2018
Disaggregation of Revenue [Abstract]
Disaggregation of Revenue [Table Text Block]	Disaggregation of Revenue The following tables present revenues on a disaggregated basis, in a manner that reconciles with the Company's reportable segment disclosures, for the following categories: product versus service type, customer type, contract type, and major program. See Note 9: Segment Information. The Company believes that this level of disaggregation provides investors with information to evaluate the Company’s financial performance and provides the Company with information to make capital allocation decisions in the most appropriate manner. Year Ended December 31, 2018 ($ in millions) Ingalls Newport News Technical Solutions Intersegment Eliminations Total Revenue Type Product sales $ 2,390 $ 3,559 $ 74 $ — $ 6,023 Service revenues 215 1,156 782 — 2,153 Intersegment 2 7 132 (141 ) — Sales and service revenues $ 2,607 $ 4,722 $ 988 $ (141 ) $ 8,176 Customer Type Federal $ 2,605 $ 4,714 $ 589 $ — $ 7,908 Commercial — 1 265 — 266 State and local government agencies — — 2 — 2 Intersegment 2 7 132 (141 ) — Sales and service revenues $ 2,607 $ 4,722 $ 988 $ (141 ) $ 8,176 Contract Type Firm fixed-price $ 81 $ 8 $ 147 $ — $ 236 Fixed-price incentive 2,167 1,876 1 — 4,044 Cost-type 357 2,831 370 — 3,558 Time and materials — — 338 — 338 Intersegment 2 7 132 (141 ) — Sales and service revenues $ 2,607 $ 4,722 $ 988 $ (141 ) $ 8,176 Year Ended December 31 ($ in millions) 2018 Major Programs Amphibious assault ships $ 1,348 Surface combatants and coast guard cutters 1,253 Other 6 Total Ingalls 2,607 Aircraft carriers 2,605 Submarines 1,476 Other 641 Total Newport News 4,722 Government and energy services 799 Oil and gas services 189 Total Technical Solutions 988 Intersegment eliminations (141 ) Sales and service revenues $ 8,176

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Segment Operating Profit (Loss) Reconciliation [Table Text Block]	Results of Operations by Segment The following table presents the Company's operating results by segment. Year Ended December 31 ($ in millions) 2018 2017 2016 Sales and Service Revenues Ingalls $ 2,607 $ 2,420 $ 2,389 Newport News 4,722 4,164 4,089 Technical Solutions 988 952 691 Intersegment eliminations (141 ) (95 ) (101 ) Total sales and service revenues $ 8,176 $ 7,441 $ 7,068 Operating Income Ingalls $ 313 $ 313 $ 321 Newport News 318 354 386 Technical Solutions 32 21 8 Total segment operating income 663 688 715 Non-segment factors affecting operating income Operating FAS/CAS Adjustment 290 205 163 Non-current state income taxes (2 ) (12 ) (2 ) Total operating income $ 951 $ 881 $ 876
Segment Assets Reconciliation [Table Text Block]	The following tables present the Company's assets, capital expenditures, and depreciation and amortization by segment. December 31 ($ in millions) 2018 2017 2016 Assets Ingalls $ 1,448 $ 1,385 1,362 Newport News 3,572 3,350 3,169 Technical Solutions 734 642 692 Corporate 629 997 1,129 Total assets $ 6,383 $ 6,374 $ 6,352
Segment Other Significant Items Reconciliation [Table Text Block]	Year Ended December 31 ($ in millions) 2018 2017 2016 Capital Expenditures (1) Ingalls $ 134 $ 131 $ 97 Newport News 258 224 176 Technical Solutions 9 6 8 Corporate 1 — 4 Total capital expenditures $ 402 $ 361 $ 285 (1) Net of grant proceeds for capital expenditures Year Ended December 31 ($ in millions) 2018 2017 2016 Depreciation and Amortization (1) Ingalls $ 69 $ 73 $ 68 Newport News 113 107 109 Technical Solutions 21 25 9 Total depreciation and amortization $ 203 $ 205 $ 186 (1) Excluding amortization of debt issuance costs

Accounts Receivable and Contr_2

Accounts Receivable and Contract Assets (Tables)	12 Months Ended
	Dec. 31, 2018
Receivables [Abstract]
Accounts receivable, net	Accounts receivable were comprised of the following: December 31 ($ in millions) 2018 2017 Due from U.S. Government $ 216 $ 275 Due from other customers 45 167 Total accounts receivable 261 442 Allowances for doubtful accounts (9 ) (13 ) Total accounts receivable, net $ 252 $ 429
Contract assets	Contract assets were comprised of the following: December 31 ($ in millions) 2018 2017 Due from U.S. Government $ 899 $ 733 Due from other customers 104 26 Total contract assets 1,003 759

Inventoried Costs, Net (Tables)

Inventoried Costs, Net (Tables)	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Inventoried costs, net	Inventoried costs were comprised of the following: December 31 ($ in millions) 2018 2017 Production costs of contracts in process (1) $ 34 $ 90 Raw material inventory 94 93 Total inventoried costs, net $ 128 $ 183 (1) Includes amounts capitalized pursuant to applicable provisions of the FAR and CAS.

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Change in Carrying Amount of Goodwill	For the years ended December 31, 2018 and 2017 , the carrying amounts of goodwill changed as follows: ($ in millions) Ingalls Newport News Technical Solutions Total Balance as of December 31, 2016 $ 175 $ 721 $ 338 $ 1,234 Adjustments — — (17 ) (17 ) Balance as of December 31, 2017 175 721 321 1,217 Acquisitions — — 46 46 Balance as of December 31, 2018 $ 175 $ 721 $ 367 $ 1,263

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal Income Tax Expense	Federal and foreign income tax expense for the years ended December 31, 2018 , 2017 , and 2016 , consisted of the following: Year Ended December 31 ($ in millions) 2018 2017 2016 Income Taxes on Operations Federal and foreign income taxes currently payable $ 127 $ 121 $ 134 Change in deferred federal and foreign income taxes 8 172 77 Total federal and foreign income taxes $ 135 $ 293 $ 211
Reconciliation of Income Tax Expense to Federal Statutory Rate	Income tax expense differed from the amount based on the statutory federal income tax rate applied to earnings (loss) before income taxes due to the following: Year Ended December 31 ($ in millions) 2018 2017 2016 Income tax expense (benefit) on operations at statutory rate $ 204 $ 270 $ 274 Provisional deferred tax asset revaluation - Tax Act (10 ) 56 — Stock compensation - net excess tax benefits (5 ) (25 ) (29 ) Manufacturing deduction — (12 ) (21 ) Uncertain tax positions 25 — (15 ) Research and development tax credit (80 ) — — Other, Net 1 4 2 Total federal and foreign income taxes $ 135 $ 293 $ 211
Change in Unrecognized Tax Benefits	The changes in unrecognized tax benefits (exclusive of interest and penalties) for the years ended December 31, 2018 , 2017 , and 2016 are summarized in the following table: December 31 ($ in millions) 2018 2017 2016 Unrecognized tax benefits at beginning of the year $ — $ 2 $ 27 Additions based on tax positions related to the current year 3 — 1 Additions based on tax positions related to prior years 22 — 2 Reductions based on tax positions related to prior years — — (15 ) Settlements — — (11 ) Statute of limitation expirations — (2 ) (2 ) Net change in unrecognized tax benefits 25 (2 ) (25 ) Unrecognized tax benefits at end of the year $ 25 $ — 2
Summary of Income Tax Examinations	The following table summarizes the tax years that are either currently under examination or remain open under the applicable statute of limitations and subject to examination by the major tax jurisdictions in which the Company operates: Jurisdiction Years United States (1) 2011 - 2017 Connecticut 2016 - 2017 Mississippi 2012 - 2017 Virginia (1) 2011 - 2017 (1) The 2014 tax year has been closed in these jurisdictions.
Net Deferred Tax Assets	The tax effects of significant temporary differences and carry-forwards that gave rise to year-end deferred tax balances, as presented in the consolidated statements of financial position, were as follows: December 31 ($ in millions) 2018 2017 Deferred Tax Assets Retirement benefits $ 331 $ 263 Workers' compensation 151 167 Reserves not currently deductible for tax purposes 52 44 Stock-based compensation 10 11 Net operating losses and tax credit carry-forwards 19 21 Other 5 — Gross deferred tax assets 568 506 Less valuation allowance 12 12 Net deferred tax assets 556 494 Deferred Tax Liabilities Depreciation and amortization 247 223 Contract accounting differences 43 51 Purchased intangibles 103 106 Gross deferred tax liabilities 393 380 Total net deferred tax assets $ 163 $ 114

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Schedule of Long-term Debt	Long-term debt consisted of the following: December 31 ($ in millions) 2018 2017 Senior notes due November 15, 2025, 5.000% 600 600 Senior notes due December 1, 2027, 3.483% 600 600 Mississippi economic development revenue bonds due May 1, 2024, 7.81% 84 84 Gulf opportunity zone industrial development revenue bonds due December 1, 2028, 4.55% 21 21 Less unamortized debt issuance costs (22 ) (26 ) Total long-term debt 1,283 1,279
Schedule of Extinguishment of Debt [Table Text Block]	Details of the loss on early extinguishment of debt related to the Company's prior credit facility and refinancing of senior notes, which was included in interest expense, were as follows: Year Ended ($ in millions) December 31, 2017 Redemption and tender premiums and fees $ 15 Write-off of unamortized debt issuance costs 7 Total loss on early extinguishment of debt $ 22

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Minimum Rental Commitments Under Long-Term Non-Cancellable Operating Leases	The amounts of minimum rental commitments under long-term non-cancellable operating leases for each of the years 2019 through 2023 and thereafter are: ($ in millions) 2019 $ 41 2020 36 2021 30 2022 20 2023 13 Thereafter 56 Total $ 196

Employee Pension and Other Po_2

Employee Pension and Other Postretirement Benefits Employee Pension and Other Postretirement Benefits (Tables)	12 Months Ended
	Dec. 31, 2018
Retirement Benefits [Abstract]
Schedule of Net Benefit Costs	The costs of the Company's defined benefit pension plans and other postretirement benefit plans for the years ended December 31, 2018 , 2017 , and 2016 , were as follows: Pension Benefits Other Benefits Year Ended December 31 Year Ended December 31 ($ in millions) 2018 2017 2016 2018 2017 2016 Components of Net Periodic Benefit Cost Service cost $ 157 $ 146 $ 133 $ 8 $ 10 $ 10 Interest cost 254 266 262 21 24 25 Expected return on plan assets (429 ) (367 ) (346 ) — — — Amortization of prior service cost (credit) 24 20 18 (22 ) (20 ) (19 ) Amortization of net actuarial loss (gain) 81 97 84 (3 ) (4 ) (6 ) Net periodic benefit cost $ 87 $ 162 $ 151 $ 4 $ 10 $ 10
Schedule of Defined Benefit Plans Disclosures	The funded status of these plans as of December 31, 2018 and 2017 , was as follows: Pension Benefits Other Benefits December 31 December 31 ($ in millions) 2018 2017 2018 2017 Change in Benefit Obligation Benefit obligation at beginning of year $ 6,778 $ 6,050 $ 553 $ 578 Service cost 157 146 8 10 Interest cost 254 266 21 24 Plan participants' contributions 6 4 8 8 Plan amendments — 74 — (10 ) Actuarial loss (gain) (441 ) 457 (73 ) (15 ) Benefits paid (235 ) (219 ) (38 ) (42 ) Benefit obligation at end of year 6,519 6,778 479 553 Change in Plan Assets Fair value of plan assets at beginning of year 5,837 4,911 — — Actual return on plan assets (398 ) 840 — — Employer contributions 516 301 30 34 Plan participants' contributions 6 4 8 8 Benefits paid (235 ) (219 ) (38 ) (42 ) Fair value of plan assets at end of year 5,726 5,837 — — Funded status $ (793 ) $ (941 ) $ (479 ) $ (553 ) Amounts Recognized in the Consolidated Statements of Financial Position: Pension plan assets (1) $ — $ 6 $ — $ — Current liability (2) (29 ) (25 ) (131 ) (139 ) Non-current liability (3) (764 ) (922 ) (348 ) (414 ) Accumulated other comprehensive loss (income) (pre-tax) related to: Prior service costs (credits) 99 122 (53 ) (75 ) Net actuarial loss (gain) 1,780 1,477 (88 ) (18 ) (1) Included in miscellaneous other assets. (2) Included in other current liabilities and current portion of postretirement plan liabilities, respectively. (3) Included in pension plan liabilities and other postretirement plan liabilities, respectively.
Schedule of Amounts Recognized in Other Comprehensive Income (Loss)	The changes in amounts recorded in accumulated other comprehensive income (loss) were as follows: Pension Benefits Other Benefits Year Ended December 31 Year Ended December 31 ($ in millions) 2018 2017 2016 2018 2017 2016 Prior service cost (credit) $ — $ (74 ) $ — $ — $ 10 $ — Amortization of prior service cost (credit) 24 20 18 (22 ) (20 ) (19 ) Net actuarial loss (gain) (386 ) 16 (241 ) 73 15 (9 ) Amortization of net actuarial loss (gain) 81 97 84 (3 ) (4 ) (6 ) Other 1 (1 ) 1 — — — Total changes in accumulated other comprehensive income (loss) $ (280 ) $ 58 $ (138 ) $ 48 $ 1 $ (34 )
Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year	The amounts included in accumulated other comprehensive income (loss) as of December 31, 2018 , expected to be recognized as components of net periodic expense in 2019 are as follows: ($ in millions) Pension Benefits Other Benefits Prior service cost (credit) $ 18 $ (22 ) Net loss 113 (11 ) Total $ 131 $ (33 )
Schedule of Assumptions Used and Health Care Cost Trend Rates	The weighted average assumptions used to determine the net periodic benefit costs for each year ended December 31 were as follows: Pension Benefits 2018 2017 2016 Discount rate 3.82 % 4.47 % 4.73 % Expected long-term rate on plan assets 7.25 % 7.25 % 7.50 % Rate of compensation increase 3.71 % 3.68 % 3.66 % Other Benefits 2018 2017 2016 Discount rate 3.85 % 4.38 % 4.58 % Initial health care cost trend rate assumed for next year 6.00 % 6.50 % 7.00 % Gradually declining to a rate of 4.50 % 5.00 % 5.00 % Year in which the rate reaches the ultimate rate 2025 2025 2024 The weighted average assumptions used to determine the benefit obligations as of December 31 of each year were as follows: Pension Benefits Other Benefits December 31 December 31 2018 2017 2018 2017 Discount rate 4.34 % 3.82 % 4.33 % 3.85 % Rate of compensation increase 3.67 % 3.71 % Initial health care cost trend rate assumed for next year 5.50 % 6.00 % Gradually declining to a rate of 4.50 % 4.50 % Year in which the rate reaches the ultimate rate 2024 2025
Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates	A one percent change in the assumed health care cost trend rates would have the following effects on 2018 results: 1 Percentage Point ($ in millions) Increase Decrease Effect on postretirement benefit expense $ 2 $ (2 ) Effect on postretirement benefit obligations 22 (20 )
Schedule of Defined Benefit Plans Disclosures, Cash Contributions	The Company made the following contributions to its pension plans and other postretirement plans for the years ended December 31, 2018 , 2017 , and 2016 : Year Ended December 31 ($ in millions) 2018 2017 2016 Pension plans Discretionary Qualified $ 508 $ 294 $ 167 Non-qualified 8 7 6 Other benefit plans 30 34 32 Total contributions $ 546 $ 335 $ 205
Schedule of Expected Benefit Payments and Prescription Drug Subsidy Receipts	The following table presents estimated future benefit payments, using the same assumptions used in determining the Company's benefit obligations as of December 31, 2018 . Benefit payments depend on future employment and compensation levels, years of service, and mortality. Changes in any of these factors could significantly affect these estimated amounts. Other Benefits ($ in millions) Pension Benefits Benefit Payments Subsidy Receipts 2019 $ 254 $ 33 $ — 2020 266 35 — 2021 285 37 — 2022 306 37 — 2023 326 38 — Years 2024 to 2028 $ 1,927 $ 181 $ 2
Schedule of Allocation of Plan Assets	Certain investments that are measured at fair value using NAV per share (or its equivalent) as a practical expedient are not required to be categorized in the fair value hierarchy table. The total fair value of these investments is included in the table below to permit reconciliation of the fair value hierarchy to amounts presented in the funded status table above. December 31, 2018 ($ in millions) Total Level 1 Level 2 Level 3 Plan assets subject to leveling U.S. and international equities $ 1,174 $ 1,174 $ — $ — Government and agency debt securities 433 — 433 — Corporate and other debt securities 1,265 — 1,265 — Group annuity contract 3 — 3 — Cash and cash equivalents, net — — — — Net plan assets subject to leveling $ 2,875 $ 1,174 $ 1,701 $ — Plan assets not subject to leveling U.S. and international equities (a) 1,910 Corporate and other debt securities 193 Real estate investments 302 Private partnerships 48 Hedge funds 287 Cash and cash equivalents, net (b) 111 Total plan assets not subject to leveling 2,851 Net plan assets $ 5,726 (a) U.S. and international equity securities include investments in small, medium, and large capitalization stocks of public companies held in commingled trust funds. (b) Cash and cash equivalents are liquid short-term investment funds and include net receivables and payables of the trust. These funds are available for immediate use to fund daily operations, execute investment policies, and serve as a temporary investment vehicle. December 31, 2017 ($ in millions) Total Level 1 Level 2 Level 3 Plan assets subject to leveling U.S. and international equities $ 1,270 $ 1,270 $ — $ — Government and agency debt securities 409 — 409 — Corporate and other debt securities 1,287 — 1,287 — Group annuity contract 3 — 3 — Cash and cash equivalents, net — — — — Net plan assets subject to leveling $ 2,969 $ 1,270 $ 1,699 $ — Plan assets not subject to leveling U.S. and international equities (a) 2,012 Corporate and other debt securities 165 Real estate investments 279 Private partnerships 16 Hedge funds 281 Cash and cash equivalents, net (b) 115 Total plan assets not subject to leveling 2,868 Net plan assets $ 5,837 (a) U.S. and international equity securities include investments in small, medium, and large capitalization stocks of public companies held in commingled trust funds. (b) Cash and cash equivalents are liquid short-term investment funds and include net receivables and payables of the trust. These funds are available for immediate use to fund daily operations, execute investment policies, and serve as a temporary investment vehicle. The Investment Committee has set the minimum and maximum permitted values for each asset class in the Company's pension plan master trust for the year ended December 31, 2018 , as follows: Range U.S. equities 15 - 36% International equities 10 - 29% Fixed income securities 25 - 50% Alternative investments 10 - 25%

Stock Compensation Plans (Table

Stock Compensation Plans (Tables)	12 Months Ended
	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Status of Stock Awards	The stock award activity for the years ended December 31, 2018 , 2017 , and 2016 , was as follows: Stock Awards (in thousands) Weighted-Average Grant Date Fair Value Weighted Average Remaining Contractual Term Outstanding as of December 31, 2015 891 $ 75.73 0.6 years Granted 169 134.78 Adjustment due to performance 326 46.75 Vested (783 ) 46.75 Forfeited (25 ) 127.45 Outstanding as of December 31, 2016 578 113.95 0.8 years Granted 109 217.02 Adjustment due to performance 163 97.00 Vested (387 ) 97.00 Forfeited (14 ) 154.75 Outstanding as of December 31, 2017 449 147.13 0.8 years Granted 99 259.62 Adjustment due to performance 98 142.85 Vested (235 ) 142.85 Forfeited (12 ) 218.50 Outstanding as of December 31, 2018 399 $ 174.07 0.7 years
Schedule of Status of Stock Options	The stock option activity for the years ended December 31, 2018 , 2017 , and 2016 , was as follows: Shares Under Option (in thousands) Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (in years) Aggregate Intrinsic Value ($ in millions) Outstanding as of December 31, 2015 533 $ 33.90 0.6 years $ 50 Exercised (271 ) 30.20 Outstanding as of December 31, 2016 262 37.73 0.1 years 38 Exercised (262 ) 37.73 Outstanding as of December 31, 2017 — — — Outstanding as of December 31, 2018 — $ — $ — Vested as of December 31, 2018 — $ — $ —

Unaudited Selected Quarterly _2

Unaudited Selected Quarterly Data (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Unaudited Quarterly Financial Results	Unaudited quarterly financial results for the years ended December 31, 2018 and 2017 , are set forth in the following tables: Year Ended December 31, 2018 ($ in millions, except per share amounts) 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Sales and service revenues $ 1,874 $ 2,020 $ 2,083 $ 2,199 Operating income 191 257 290 213 Earnings before income taxes 195 262 295 219 Net earnings 156 239 229 212 Dividends declared per share $ 0.72 $ 0.72 $ 0.72 $ 0.86 Basic earnings per share $ 3.48 $ 5.41 $ 5.29 $ 4.96 Diluted earnings per share $ 3.48 $ 5.40 $ 5.29 $ 4.94 Year Ended December 31, 2017 ($ in millions, except per share amounts) 1st Qtr 2nd Qtr (1) 3rd Qtr 4th Qtr (2) Sales and service revenues $ 1,724 $ 1,858 $ 1,863 $ 1,996 Operating income 168 241 241 231 Earnings before income taxes 147 218 220 187 Net earnings 119 147 149 64 Dividends declared per share $ 0.60 $ 0.60 $ 0.60 $ 0.72 Basic earnings per share $ 2.57 $ 3.22 $ 3.28 $ 1.41 Diluted earnings per share $ 2.56 $ 3.21 $ 3.27 $ 1.41 (1) In the second quarter of 2017, the Company recorded a $30 million favorable cumulative adjustment on a contract at the Ingalls segment. (2) In the fourth quarter of 2017, the Tax Act resulted in an increase of $56 million to the Company's income tax expense.

Description of Business (Narrat

Description of Business (Narrative) (Details)	12 Months Ended
	Dec. 31, 2018segments
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating segments	3

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Deferred gain on receipt of grant	$ 61	$ 21	$ 15
Grants received	61	21	30
Other income and gains	14		15
Independent research and development	25	17	$ 19
Assets Held-in-trust [Abstract]
Assets held in rabbi trusts	$ 109	$ 94
Federal Statutory Income Tax Rate, Percent	21.00%	35.00%
Deferred tax asset valuation allowance	$ 12	$ 12
Percent likliehood of unfavorable settlement of uncertain income tax benefit	50.00%
Maturity period of cash equivalents	90 days
Concentration Risk [Line Items]
Workers' Compensation Discount, Percent	2.89%	2.35%
Workers' compensation benefit obligations on an undiscounted basis	$ 845	$ 925
Loans Receivable, Net	38
Receivable with Imputed Interest, Discount	$ 10
Amortization threshold for actuarial gains (losses)	10.00%
Maximum | Self-Insured Group Medical Insurance Risk [Member] | Other Current Liabilities [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	5.00%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies Schedule of Depreciable Assets (Table) (Details)	12 Months Ended
	Dec. 31, 2018
Land improvements | Minimum
Property, Plant and Equipment
Useful life	2 years
Land improvements | Maximum
Property, Plant and Equipment
Useful life	40 years
Buildings and improvements | Minimum
Property, Plant and Equipment
Useful life	2 years
Buildings and improvements | Maximum
Property, Plant and Equipment
Useful life	60 years
Capitalized software costs | Minimum
Property, Plant and Equipment
Useful life	3 years
Capitalized software costs | Maximum
Property, Plant and Equipment
Useful life	9 years
Machinery and other equipment | Minimum
Property, Plant and Equipment
Useful life	2 years
Machinery and other equipment | Maximum
Property, Plant and Equipment
Useful life	45 years

Summary of Significant Accoun_6

Summary of Significant Accounting Policies Related Party Transactions (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018
Related Party Transaction [Line Items]
Long-term debt	$ 1,279	$ 1,283
Former Parent [Member] | Spin-off Related Agreements [Member]
Related Party Transaction [Line Items]
Related Party Transactions, Received from Affiliates		8
Northrop Grumman [Member] | Former Parent [Member] | Tax Matters Agreement [Member]
Related Party Transaction [Line Items]
Related Party Tax Expense, Due from Affiliates, Deferred	8
Mississippi economic development revenue bonds due May 1, 2024, 7.81% | Bonds
Related Party Transaction [Line Items]
Long-term debt	$ 84	$ 84

Accounting Standards Updates (N

Accounting Standards Updates (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended										12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017		Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Item Effected [Line Items]
Federal and foreign income taxes											$ 135	$ 293	$ 211
Sales and service revenues	$ 2,199	$ 2,083	$ 2,020	$ 1,874	$ 1,996		$ 1,863	$ 1,858		$ 1,724	8,176	7,441	7,068
Operating income (loss)	213	290	257	191	231		241	241	[1]	168	951	881	876
Net earnings (loss)	$ 212	$ 229	$ 239	$ 156	$ 64	[2]	$ 149	$ 147	[1]	$ 119	$ 836	$ 479	$ 573
Diluted earnings (loss) per share	$ 4.94	$ 5.29	$ 5.40	$ 3.48	$ 1.41	[2]	$ 3.27	$ 3.21	[1]	$ 2.56	$ 19.09	$ 10.46	$ 12.14
Accounting Standards Update 2014-09 [Member]
Item Effected [Line Items]
Retention Receivable					$ 64							$ 64
Cumulative Effect on Retained Earnings, Net of Tax												5
Federal and foreign income taxes												1
Operating income (loss)											$ 1
Net earnings (loss)											$ 1
Diluted earnings (loss) per share											$ 0.01
Product [Member]
Item Effected [Line Items]
Sales and service revenues											$ 6,023	$ 5,573	$ 5,631
Product [Member] | Accounting Standards Update 2014-09 [Member]
Item Effected [Line Items]
Sales and service revenues											1
Minimum
Item Effected [Line Items]
Operating Lease, Right-of-Use Asset	$ 200										200
Operating Lease, Liability	200										200
Maximum
Item Effected [Line Items]
Operating Lease, Right-of-Use Asset	220										220
Operating Lease, Liability	$ 220										$ 220
[1]	(1) In the second quarter of 2017, the Company recorded a $30 million favorable cumulative adjustment on a contract at the Ingalls segment.
[2]	(2) In the fourth quarter of 2017, the Tax Act resulted in an increase of $56 million to the Company's income tax expense.

Accounting Standards Updates _2

Accounting Standards Updates (Table) (Details) - USD ($) $ in Millions	3 Months Ended										12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017		Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sales and service revenues	$ 2,199	$ 2,083	$ 2,020	$ 1,874	$ 1,996		$ 1,863	$ 1,858		$ 1,724	$ 8,176	$ 7,441	$ 7,068
Cost of sales and service revenues
Income (loss) from operating investments, net											17	12	6
Other income and gains											14		15
General and administrative expenses											871	759	768
Operating income (loss)	213	290	257	191	231		241	241	[1]	168	951	881	876
Other income (expense)
Interest Expense											(58)	(94)	(74)
Non-operating retirement FAS expense											74	(16)	(18)
Other, net											4	1
Earnings (loss) before income taxes	219	295	262	195	187		220	218	[1]	147	971	772	784
Federal and foreign income taxes											135	293	211
Net earnings (loss)	$ 212	$ 229	$ 239	$ 156	$ 64	[2]	$ 149	$ 147	[1]	$ 119	836	479	573
Product [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sales and service revenues											6,023	5,573	5,631
Cost of sales and service revenues
Cost of sales and services revenues											4,627	4,277	4,237
Service [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sales and service revenues											2,153	1,868	1,437
Cost of sales and service revenues
Cost of sales and services revenues											$ 1,758	1,536	1,208
Previous Accounting Guidance [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sales and service revenues												7,441	7,068
Cost of sales and service revenues
Income (loss) from operating investments, net												12	6
Other income and gains													15
General and administrative expenses												570	623
Operating income (loss)												865	858
Other income (expense)
Interest Expense												(94)	(74)
Other, net												1
Earnings (loss) before income taxes												772	784
Federal and foreign income taxes												293	211
Net earnings (loss)												479	573
Previous Accounting Guidance [Member] | Product [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sales and service revenues												5,573	5,631
Cost of sales and service revenues
Cost of sales and services revenues												4,444	4,380
Previous Accounting Guidance [Member] | Service [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Sales and service revenues												1,868	1,437
Cost of sales and service revenues
Cost of sales and services revenues												$ 1,574	$ 1,228
[1]	(1) In the second quarter of 2017, the Company recorded a $30 million favorable cumulative adjustment on a contract at the Ingalls segment.
[2]	(2) In the fourth quarter of 2017, the Tax Act resulted in an increase of $56 million to the Company's income tax expense.

Avondale and Gulfport (Narrativ

Avondale and Gulfport (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2015	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Amortization of Restructuring Costs, Period	5 years
Facility Closing | Gulfport [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Cost Incurred to Date	$ 54
Restructuring and Related Cost, Accelerated Depreciation	$ 52
Gain on Disposal		$ 9
Facility Closing | Avondale Wind Down
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Costs, Allowable			$ 251
Financing receivable, contractual term	9 years
Gains (Losses) on Sales of Other Real Estate	$ 7

Acquisitions (Narrative) (Detai

Acquisitions (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended									12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017		Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired										$ 77	$ (3)	$ 372
Goodwill, Acquired During Period										46
Sales and service revenues	$ 2,199	$ 2,083	$ 2,020	$ 1,874	$ 1,996	$ 1,863	$ 1,858		$ 1,724	8,176	7,441	7,068
Operating income (loss)	213	$ 290	$ 257	$ 191	$ 231	$ 241	$ 241	[1]	$ 168	951	881	876
Goodwill deductible for tax purposes	201									201
G2, Inc. [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired										77
Cash Acquired from Acquisition										2
Goodwill, Acquired During Period										46
Intangible assets	$ 20									20
Camber Corporation [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired												369
Cash Acquired from Acquisition												27
Goodwill, Acquired During Period												261
Intangible assets												$ 76
Sales and service revenues										315	309
Operating income (loss)										$ 12	8
Goodwill, Purchase Accounting Adjustments											$ 17
[1]	(1) In the second quarter of 2017, the Company recorded a $30 million favorable cumulative adjustment on a contract at the Ingalls segment.

Stockholders' Equity (Narrative

Stockholders' Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended										12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Nov. 07, 2017	Oct. 31, 2015
Class of Stock [Line Items]
Amount authorized for stock repurchase program														$ 2,200	$ 1,200
Repurchased shares of treasury stock											3,620,916	1,417,808	1,266,192
Treasury stock activity											$ 788	$ 288	$ 192
Treasury stock not yet settled for cash											$ 48	$ 2
Dividends declared per share	$ 0.86	$ 0.72	$ 0.72	$ 0.72	$ 0.72	$ 0.60	$ 0.60	$ 0.60	$ 0.60	$ 0.50	$ 3.02	$ 2.52	$ 2.10
Dividends declared											$ 132	$ 115	$ 98
Accumulated other comprehensive income (loss)	$ (1,288)				$ (900)				$ (951)	$ (845)	(1,288)	(900)	(951)
Defined Benefit Plans
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	(1,283)				(906)				(948)	(843)	(1,283)	(906)	(948)
Unrealized Investment Gain (Loss)
Class of Stock [Line Items]
Accumulated other comprehensive income (loss)	$ (5)				$ 6				$ (3)	$ (2)	$ (5)	$ 6	$ (3)

Stockholders' Equity Accumulate

Stockholders' Equity Accumulated Other Comprehensive Income (Loss) (Table) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning		$ (900)	$ (951)	$ (845)
Other comprehensive income (loss) before reclassifications		(314)	(20)	(250)
Amortization of prior service cost (credit)	[1]	2		(1)
Amortization of net actuarial loss (gain)	[1]	78	93	78
Tax benefit (expense) for items of other comprehensive income		59	(22)	67
Net current period other comprehensive income (loss)		(175)	51	(106)
Cumulative Effect of ASU 2016-01 - AOCI	[2]	(11)
Cumulative Effect of ASU 2018-02 - AOCI	[3]	(202)
Balance, ending		(1,288)	(900)	(951)
Income tax expense (benefit)		135	293	211
Defined Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning		(906)	(948)	(843)
Other comprehensive income (loss) before reclassifications		(312)	(34)	(249)
Amortization of prior service cost (credit)	[1]	2		(1)
Amortization of net actuarial loss (gain)	[1]	78	93	78
Tax benefit (expense) for items of other comprehensive income		59	(17)	67
Net current period other comprehensive income (loss)		(173)	42	(105)
Cumulative Effect of ASU 2018-02 - AOCI	[3]	(204)
Balance, ending		(1,283)	(906)	(948)
Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance, beginning		6	(3)	(2)
Other comprehensive income (loss) before reclassifications		(2)	14	(1)
Tax benefit (expense) for items of other comprehensive income			(5)
Net current period other comprehensive income (loss)		(2)	9	(1)
Cumulative Effect of ASU 2016-01 - AOCI	[2]	(11)
Cumulative Effect of ASU 2018-02 - AOCI	[3]	2
Balance, ending		(5)	6	(3)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income tax expense (benefit)		21	$ 36	$ 27
Accounting Standards Update 2016-01 [Member] | Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income tax expense (benefit)		$ 4
[1]	These accumulated comprehensive loss components are included in the computation of net periodic benefit cost. See Note 17: Employee Pension and Other Postretirement Benefits. The tax expense associated with amounts reclassified from accumulated other comprehensive loss for the years ended December 31, 2018, 2017, and 2016, was $21 million, $36 million, and $27 million, respectively.
[2]	The Company adopted ASU 2016-01 as of January 1, 2018. Accordingly, accumulated other comprehensive income of $11 million related to available-for-sale securities, net of $4 million tax expense, was reclassified to retained earnings.
[3]	The Company adopted ASU 2018-02 as of January 1, 2018. Accordingly, stranded tax effects of $202 million related to the Tax Act were reclassified to retained earnings.

Basic and Diluted Earnings Per

Basic and Diluted Earnings Per Share (Table) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended										12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	[1]	Sep. 30, 2017	Jun. 30, 2017	[2]	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share, Basic and Diluted [Abstract]
Net earnings (loss)	$ 212	$ 229	$ 239	$ 156	$ 64		$ 149	$ 147		$ 119	$ 836	$ 479	$ 573
Weighted-average common shares outstanding (in shares)											43.8	45.7	46.8
Net effect of dilutive												0.1	0.4
Dilutive weighted-average common shares outstanding											43.8	45.8	47.2
Earnings (loss) per share - basic	$ 4.96	$ 5.29	$ 5.41	$ 3.48	$ 1.41		$ 3.28	$ 3.22		$ 2.57	$ 19.09	$ 10.48	$ 12.24
Earnings (loss) per share - diluted	$ 4.94	$ 5.29	$ 5.40	$ 3.48	$ 1.41		$ 3.27	$ 3.21		$ 2.56	$ 19.09	$ 10.46	$ 12.14
[1]	(2) In the fourth quarter of 2017, the Tax Act resulted in an increase of $56 million to the Company's income tax expense.
[2]	(1) In the second quarter of 2017, the Company recorded a $30 million favorable cumulative adjustment on a contract at the Ingalls segment.

Earnings Per Share (Narrative)

Earnings Per Share (Narrative) (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restricted performance stock rights
Securities Excluded from Computation of Earnings Per Share
Securities excluded from computation of earnings per share	0.3	0.3	0.3
Stock Options
Securities Excluded from Computation of Earnings Per Share
Securities excluded from computation of earnings per share			0.1

Revenue (Table) (Details)

Revenue (Table) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Sales and service revenues	$ 2,199	$ 2,083	$ 2,020	$ 1,874	$ 1,996	$ 1,863	$ 1,858	$ 1,724	$ 8,176	$ 7,441	$ 7,068
Product [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									6,023	5,573	5,631
Service [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2,153	1,868	1,437
Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2,607	2,420	2,389
Sales Revenue, Intersegment, Net									2
Ingalls [Member] | Product [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2,390
Ingalls [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									215
Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									4,722	4,164	4,089
Sales Revenue, Intersegment, Net									7
Newport News Shipbuilding [Member] | Product [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									3,559
Newport News Shipbuilding [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									1,156
Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									988	952	691
Sales Revenue, Intersegment, Net									132
Technical Solutions [Member] | Product [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									74
Technical Solutions [Member] | Service [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									782
Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									(141)	$ (95)	$ (101)
Sales Revenue, Intersegment, Net									(141)
U.S. Federal Government [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									7,908
U.S. Federal Government [Member] | Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2,605
U.S. Federal Government [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									4,714
U.S. Federal Government [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									589
Commercial [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									266
Commercial [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									1
Commercial [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									265
State and Local Government agency [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2
State and Local Government agency [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2
Intersegment [Member] | Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2
Intersegment [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									7
Intersegment [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									132
Intersegment [Member] | Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									(141)
Fixed-price Contract [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									236
Fixed-price Contract [Member] | Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									81
Fixed-price Contract [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									8
Fixed-price Contract [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									147
Fixed-price incentive [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									4,044
Fixed-price incentive [Member] | Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2,167
Fixed-price incentive [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									1,876
Fixed-price incentive [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									1
Cost-type [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									3,558
Cost-type [Member] | Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									357
Cost-type [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2,831
Cost-type [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									370
Time-and-materials Contract [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									338
Time-and-materials Contract [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									338
Intersegment [Member] | Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2
Intersegment [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									7
Intersegment [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									132
Intersegment [Member] | Intersegment Eliminations [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									(141)
Amphibious assault ships [Member] | Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									1,348
Surface combatants and coast guard cutters [Member] | Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									1,253
Other programs [Member] | Ingalls [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									6
Other programs [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									641
Aircraft carriers [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									2,605
Submarines [Member] | Newport News Shipbuilding [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									1,476
Government and energy services [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									799
Oil and gas services [Member] | Technical Solutions [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues									$ 189

Revenue (Narrative) (Details)

Revenue (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue Recognition and Deferred Revenue [Abstract]
Revenue, Remaining Performance Obligation, Amount		$ 23,000
Revenue, performance obligation, recognition percentage, year one		30.00%
Revenue, performance obligation, recognition percentage, year three		40.00%
Increase (Decrease) in Net Contract Assets		$ 59
Contract with Customer, Liability, Revenue Recognized		85
Contracts Accounted for under Percentage of Completion
Change in Accounting Estimate [Line Items]
Increase (decrease) in operating income due to net cumulative catch-up adjustments		$ 110	$ 204	$ 224
Change in Accounting Estimate, Effect of Change on Operating Results, Per Share, Diluted		$ 1.99	$ 2.90	$ 3.08
Ingalls contract [Member]
Change in Accounting Estimate [Line Items]
Increase (decrease) in operating income due to net cumulative catch-up adjustments	$ 30			$ 74
Change in Accounting Estimate, Effect of Change on Operating Results, Per Share, Diluted				$ 1.02

Segment Information (Narrative)

Segment Information (Narrative) (Details) - segments	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Number of Reportable Segments	3
Minimum | Government Contracts Concentration Risk | Sales Revenue, Net
Segment Reporting Information [Line Items]
Concentration Risk, Percentage	95.00%	95.00%	95.00%

Segment Operating Profit (Loss)

Segment Operating Profit (Loss) Reconciliation (Table) (Details) - USD ($) $ in Millions	3 Months Ended									12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017		Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Sales and service revenues	$ 2,199	$ 2,083	$ 2,020	$ 1,874	$ 1,996	$ 1,863	$ 1,858		$ 1,724	$ 8,176	$ 7,441	$ 7,068
Operating income (loss)	$ 213	$ 290	$ 257	$ 191	$ 231	$ 241	$ 241	[1]	$ 168	951	881	876
Ingalls [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Sales and service revenues										2,607	2,420	2,389
Operating income (loss)										313	313	321
Newport News Shipbuilding [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Sales and service revenues										4,722	4,164	4,089
Operating income (loss)										318	354	386
Technical Solutions [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Sales and service revenues										988	952	691
Operating income (loss)										32	21	8
Intersegment Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Sales and service revenues										(141)	(95)	(101)
Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating income (loss)										663	688	715
Segment Reconciling Items [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
FAS/CAS Adjustment										290	205	163
Deferred state income taxes										$ (2)	$ (12)	$ (2)
[1]	(1) In the second quarter of 2017, the Company recorded a $30 million favorable cumulative adjustment on a contract at the Ingalls segment.

Segment Information Segment Ass

Segment Information Segment Assets Reconciliation (Table) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 6,383	$ 6,374	$ 6,352
Ingalls [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	1,448	1,385	1,362
Newport News Shipbuilding [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	3,572	3,350	3,169
Technical Solutions [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	734	642	692
Corporate Segment [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 629	$ 997	$ 1,129

Segment Information Segment Oth

Segment Information Segment Other Significant Items Reconciliation (Table) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]	$ 402	$ 361	$ 285
Depreciation and amortization	[2]	203	205	186
Ingalls [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]	134	131	97
Depreciation and amortization	[2]	69	73	68
Newport News Shipbuilding [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]	258	224	176
Depreciation and amortization	[2]	113	107	109
Technical Solutions [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]	9	6	8
Depreciation and amortization	[2]	21	$ 25	9
Corporate Segment [Member]
Segment Reporting, Other Significant Reconciling Item [Line Items]
Capital Expenditures	[1]	$ 1		$ 4
[1]	Net of grant proceeds for capital expenditures
[2]	Excluding amortization of debt issuance costs

Accounts Receivable, Net (Table

Accounts Receivable, Net (Table) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable	$ 261	$ 442
Allowance for doubtful accounts	(9)	(13)
Total accounts receivable, net	252	429
Due From U.S. Government
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amounts billed	216	275
Due From Other Customers
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amounts billed	$ 45	$ 167

Contract Assets (Table) (Detail

Contract Assets (Table) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contract assets	$ 1,003	$ 759
Due From U.S. Government
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contract assets	899	733
Due From Other Customers
Accounts, Notes, Loans and Financing Receivable [Line Items]
Contract assets	$ 104	$ 26

Inventoried Costs, Net (Table)

Inventoried Costs, Net (Table) (Details) - USD ($) $ in Millions		Dec. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Production costs of contracts in process	[1]	$ 34	$ 90
Raw material inventory		94	93
Total inventoried costs, net		$ 128	$ 183
[1]	Includes amounts capitalized pursuant to applicable provisions of the FAR and CAS.

Goodwill (Narrative) (Details)

Goodwill (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)reporting_unit	Dec. 31, 2017USD ($)reporting_unit	Dec. 31, 2016reporting_unit	Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2016
Goodwill [Line Items]
Number of Reporting Units | reporting_unit	4	4	4
Accumulated goodwill impairment losses	$ 2,877	$ 2,877
Goodwill, Translation and Purchase Accounting Adjustments		(17)
Ingalls [Member]
Goodwill [Line Items]
Accumulated goodwill impairment losses	1,568	1,568
Newport News Shipbuilding [Member]
Goodwill [Line Items]
Accumulated goodwill impairment losses	1,187	1,187
Technical Solutions [Member]
Goodwill [Line Items]
Accumulated goodwill impairment losses	$ 122	122
Goodwill, Translation and Purchase Accounting Adjustments		$ (17)
Minimum | Operating Segments [Member]
Goodwill [Line Items]
Minimum excess of fair value over carrying value				10.00%	10.00%	10.00%

Change in Carrying Amount of Go

Change in Carrying Amount of Goodwill (Table) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Goodwill beginning balance	$ 1,217	$ 1,234
Adjustments		(17)
Acquisitions	46
Goodwill ending balance	1,263	1,217
Ingalls [Member]
Goodwill [Roll Forward]
Goodwill beginning balance	175	175
Goodwill ending balance	175	175
Newport News Shipbuilding [Member]
Goodwill [Roll Forward]
Goodwill beginning balance	721	721
Goodwill ending balance	721	721
Technical Solutions [Member]
Goodwill [Roll Forward]
Goodwill beginning balance	321	338
Adjustments		(17)
Acquisitions	46
Goodwill ending balance	$ 367	$ 321

Other Intangible Assets (Narrat

Other Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Aggregate weighted-average amortization period	40 years
Aggregate amortization expense	$ 36	$ 40	$ 23
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2,019	37
2,020	33
2,021	30
2,022	28
2,023	24
G2, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets	$ 20
Aggregate weighted-average amortization period	7 years
Camber Corporation [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets			$ 76
Aggregate weighted-average amortization period			10 years

Income Taxes - Tax Reform (Narr

Income Taxes - Tax Reform (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Federal Statutory Income Tax Rate, Percent		21.00%	35.00%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount		$ (10)	$ 56
Reduction in income tax rate [Member]
Income Tax Contingency [Line Items]
Change in Deferred Tax Assets due to 2017 Tax Act	$ (252)		(252)
Change in Deferred Tax Liabilities due to 2017 Tax Act	(196)		(196)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	56	(10)	56
Change in Net Deferred Tax Assets due to 2017 Tax Act		10
Cumulative change in net deferred tax assets due to 2017 Tax Act		(46)
Effective Income Tax Rate, Reconciliation, Change in Enacted Tax Rate, Cumulative Amount		46
Acceleration of Depreciation [Member]
Income Tax Contingency [Line Items]
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount		4	(8)
Change in Net Deferred Tax Assets due to 2017 Tax Act	(8)	4	(8)
Cumulative change in net deferred tax assets due to 2017 Tax Act		(4)
Effective Income Tax Rate, Reconciliation, Change in Enacted Tax Rate, Cumulative Amount		(4)
Cumulative change in current income tax payable due to 2017 Tax Act		(4)
Change in Current Income Tax Payable due to 2017 Tax Act	$ (8)	$ 4	(8)
Executive Compensation [Member]
Income Tax Contingency [Line Items]
Compensation Tax Deduction Limitation			$ 1

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Effective income tax rate		13.90%	38.00%	26.90%
Cumulative Effect of ASU 2018-02 - AOCI	[1]	$ (202)
Threshhold for payment obligation resulting from tax liability related to spin off		5
Unrecognized Tax Benefits		25		$ 2	$ 27
Unrecognized Tax Benefits that Would Impact Effective Tax Rate		25	$ 1
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense		1	$ 1	2
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued		1		$ 1
Decrease in Unrecognized Tax Benefits is Reasonably Possible		$ 14
Federal Statutory Income Tax Rate, Percent		21.00%	35.00%
Spin-off Related Agreements [Member] | Former Parent [Member]
Related Party Transaction [Line Items]
Related Party Transactions, Received from Affiliates		$ 8
Northrop Grumman [Member] | Tax Matters Agreement [Member] | Former Parent [Member]
Related Party Transaction [Line Items]
Related Party Tax Expense, Due from Affiliates, Deferred			$ 8
[1]	The Company adopted ASU 2018-02 as of January 1, 2018. Accordingly, stranded tax effects of $202 million related to the Tax Act were reclassified to retained earnings.

Federal Income Tax Expense (Tab

Federal Income Tax Expense (Table) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Federal Income Tax Expense (Benefit), Continuing Operations [Abstract]
Federal and foreign income taxes currently payable	$ 127	$ 121	$ 134
Change in deferred federal and foreign income taxes	8	172	77
Total federal and foreign income taxes	$ 135	$ 293	$ 211

Reconciliation of Income Tax ex

Reconciliation of Income Tax expense to Federal Statutory Rate (Table) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Effective Federal Income Tax Reconciliation [Abstract]
Income tax expense (benefit) on operations at statutory rate	$ 204	$ 270	$ 274
Provisional deferred tax asset revaluation - Tax Act	(10)	56
Stock compensation - net excess tax benefits	(5)	(25)	(29)
Manufacturing deduction		(12)	(21)
Uncertain tax positions	25		(15)
Research and development tax credit	(80)
Other, Net	1	4	2
Total federal and foreign income taxes	$ 135	$ 293	$ 211

Change in Unrecognized Tax Bene

Change in Unrecognized Tax Benefits (Table) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits at beginning of the year		$ 2	$ 27
Additions based on tax positions related to the current year	$ 3		1
Additions based on tax positions related to prior years	22		2
Reductions based on tax positions related to prior years			(15)
Settlements			(11)
Statute of limitations expirations		(2)	(2)
Net change in unrecognized tax benefits	25	$ (2)	(25)
Unrecognized tax benefits at end of the year	$ 25		$ 2

Summary of Income Tax Examinati

Summary of Income Tax Examinations (Table) (Details)	12 Months Ended
	Dec. 31, 2018
UNITED STATES | Minimum
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,011
UNITED STATES | Maximum
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,017
CONNECTICUT | Minimum
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,016
CONNECTICUT | Maximum
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,017
MISSISSIPPI | Minimum
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,012
MISSISSIPPI | Maximum
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,017
VIRGINIA | Minimum
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,011
VIRGINIA | Maximum
Income Tax Examination [Line Items]
Income Tax Examination, Year under Examination	2,017

Net Deferred Tax Assets (Table)

Net Deferred Tax Assets (Table) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Deferred Tax Assets
Retirement benefits	$ 331	$ 263
Workers' compensation	151	167
Reserves not currently deductible for tax purposes	52	44
Stock-based compensation	10	11
Net operating losses and tax credit carry-forwards	19	21
Other	5
Gross deferred tax asset	568	506
Less valuation allowance	12	12
Net deferred tax assets	556	494
Deferred Tax Liabilities
Depreciation and amortization	247	223
Contract accounting differences	43	51
Purchased intangibles	103	106
Gross deferred tax liabilities	393	380
Total net deferred tax assets	$ 163	$ 114

Income Taxes Tax Credit Carry-F

Income Taxes Tax Credit Carry-Forwards (Narrative) (Details) - State and Local Jurisdiction [Member] $ in Millions	Dec. 31, 2018USD ($)
Operating Loss Carryforwards [Line Items]
Tax Credit Carryforward, Amount	$ 20
Deferred Tax Assets, Tax Credit Carryforwards	15
Tax Credit Carryforward, Valuation Allowance	$ 9

Schedule of Long-term Debt (Tab

Schedule of Long-term Debt (Table) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt	$ 1,283	$ 1,279
Less unamortized debt issuance costs	(22)	(26)
Long-term debt, net of current portion	1,283	1,279
Senior Note
Debt Instrument [Line Items]
Less unamortized debt issuance costs	(14)	(15)
Senior Note | Senior notes due November 15, 2025, 5.000%
Debt Instrument [Line Items]
Long-term debt	$ 600	$ 600
Stated percentage	5.00%	5.00%
Senior Note | Senior notes due December 1, 2027, 3.483%
Debt Instrument [Line Items]
Long-term debt	$ 600	$ 600
Stated percentage	3.483%	3.483%
Bonds | Mississippi economic development revenue bonds due May 1, 2024, 7.81%
Debt Instrument [Line Items]
Long-term debt	$ 84	$ 84
Stated percentage	7.81%	7.81%
Bonds | Gulf opportunity zone industrial development revenue bonds due December 1, 2028, 4.55%
Debt Instrument [Line Items]
Long-term debt	$ 21	$ 21
Stated percentage	4.55%	4.55%

Debt Credity Facility (Narrativ

Debt Credity Facility (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Credit Facility
Debt issuance costs	$ 22	$ 26
Revolving Credit Facility
Credit Facility
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,250
Line of credit term (in years)	5 years
Revolving Credit Facility | London Interbank Offered Rate (LIBOR) [Member] | Minimum
Credit Facility
Spread on variable rate (LIBOR)	1.125%
Revolving Credit Facility | London Interbank Offered Rate (LIBOR) [Member] | Maximum
Credit Facility
Spread on variable rate (LIBOR)	1.50%
Revolving Credit Facility | Base Rate [Member]
Credit Facility
Fee rate on unutilized balance	0.25%
Revolving Credit Facility | Base Rate [Member] | Minimum
Credit Facility
Fee rate on unutilized balance	0.20%
Revolving Credit Facility | Base Rate [Member] | Maximum
Credit Facility
Fee rate on unutilized balance	0.30%
Revolving Credit Facility | HII Credit Facility
Credit Facility
Revolving Credit Facility balance unutilized	$ 1,234
Debt issuance costs	8	$ 11
Letter of Credit
Credit Facility
Line of Credit Facility, Maximum Borrowing Capacity	500
Standby Letters of Credit | HII Credit Facility
Credit Facility
Letters of credit issued but undrawn	$ 16

Debt Senior Note (Narrative) (D

Debt Senior Note (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt	$ 1,283	$ 1,279
Debt issuance costs	22	26
Senior Notes
Debt Instrument [Line Items]
Debt issuance costs	14	15
Senior Notes | Senior notes due December 1, 2027, 3.483%
Debt Instrument [Line Items]
Long-term debt	$ 600	$ 600
Debt Instrument, Interest Rate, Stated Percentage	3.483%	3.483%
Senior Notes | Senior notes due December 15, 2021, 5.000%
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.00%
Senior Notes | Senior notes due November 15, 2025, 5.000%
Debt Instrument [Line Items]
Long-term debt	$ 600	$ 600
Debt Instrument, Interest Rate, Stated Percentage	5.00%	5.00%

Debt Schedule of Extinguishment

Debt Schedule of Extinguishment of Debt (Table) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017USD ($)
Extinguishment of Debt [Line Items]
Redemption and tender premiums and fees	$ 15
Write off of unamortized debt issuance costs	7
Loss on early extinguishment of debt	$ 22

Debt Revenue Bond (Narrative) (

Debt Revenue Bond (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term debt	$ 1,283	$ 1,279
Long-term Debt, Fair Value	1,292	1,361
Bonds | Mississippi economic development revenue bonds due May 1, 2024, 7.81%
Debt Instrument [Line Items]
Long-term debt	$ 84	$ 84
Debt Instrument, Interest Rate, Stated Percentage	7.81%	7.81%
Bonds | Gulf opportunity zone industrial development revenue bonds due December 1, 2028, 4.55%
Debt Instrument [Line Items]
Long-term debt	$ 21	$ 21
Debt Instrument, Interest Rate, Stated Percentage	4.55%	4.55%

Investigations, Claims, And L_2

Investigations, Claims, And Litigation (Narrative) (Details) - Bolivarian Republic of Venezuela [Member] $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)frigates
Loss Contingencies
Number of foreign-built frigates | frigates	2
Arbitration Claim	$ 151
Litigation counter claim [Member]
Loss Contingencies
Arbitration Claim	$ 22

Commitments and Contingencies_2

Commitments and Contingencies (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Commitments and Contingencies
Entity Number of Employees	40,000
Operating lease rent expense	$ 69	$ 63	$ 69
Percent of workforce subject to collective bargaining arrangements
Commitments and Contingencies
Collective bargaining agreements	.50
Number of collective bargaining agreements
Commitments and Contingencies
Collective bargaining agreements	9
Number of collective bargaining agreements at Newport News
Commitments and Contingencies
Collective bargaining agreements	4
Number of collective bargaining agreements at Pascagoula
Commitments and Contingencies
Collective bargaining agreements	5
Surety Bonds Outstanding
Commitments and Contingencies
Surety bonds outstanding	$ 275
HII Credit Facility | Standby Letters of Credit
Commitments and Contingencies
Letters of credit issued but undrawn	$ 16
Minimum
Commitments and Contingencies
Period covered by collective bargaining agreements	3 years
Maximum
Commitments and Contingencies
Period covered by collective bargaining agreements	5 years
Hanford Site, Richland, Washington
Commitments and Contingencies
Entity Number of Employees	35
Newport News Shipbuilding business systems [Member] | Maximum
Commitments and Contingencies
Potential Contract Receivable Retainage, Percent	5.00%
Newport News Shipbuilding [Member] | United Steelworkers [Member] | Percent of workforce subject to collective bargaining arrangements
Commitments and Contingencies
Collective bargaining agreements	.50

Commitments and Contingencies M

Commitments and Contingencies Minimum Rental commitments Under Long-Term Non-Cancellable Operating Leases (Table) (Details) $ in Millions	Dec. 31, 2018USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2,019	$ 41
2,020	36
2,021	30
2,022	20
2,023	13
Thereafter	56
Total	$ 196

Employee Pension and Other Po_3

Employee Pension and Other Postretirement Benefits Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Cost recognized for defined contribution plans	$ 102	$ 78	$ 71
Pension and other postretirement benefit plan liabilities	183	182
Defined Contribution Plan, Liabilities	30	32
Assets held in rabbi trusts	109	94
Fair value of plan assets	$ 5,726	$ 5,837
Initial health care cost trend rate assumed for next year	5.50%	6.00%
Gradually declining to a rate of	4.50%	4.50%
Partnership [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments	$ 132
Derivative [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4	$ 1
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	6,519	6,778	6,050
Accumulated benefit obligation	6,183	6,367
Fair value of plan assets	5,726	5,837	4,911
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation	6,519	5,386
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets	5,726	4,440
Aggregate accumulated benefit obligation for plans with accumulated benefit obligations in excess of plan assets	6,183	5,001
Aggregate fair value of plan assets for plans with accumulated benefit obligations in excess of plan assets	5,726	4,440
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	21
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 479	$ 553	$ 578
Initial health care cost trend rate assumed for next year	5.50%	6.00%
Gradually declining to a rate of	4.50%	4.50%
Defined Benefit Plan Health Care Cost Trend Rate, Year ultimate rate is reached	2,024	2,025
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 33
Maximum
Defined Benefit Plan Disclosure [Line Items]
Maximum annual percentage employer contribution per employee	4.00%
Non-qualified [Member]
Defined Benefit Plan Disclosure [Line Items]
Assets held in rabbi trusts	$ 78	$ 61
Qualified [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	6,336	6,596
Accumulated benefit obligation	6,017	6,202
Fair value of plan assets	$ 5,726	$ 5,837

Employee Pension and Other Po_4

Employee Pension and Other Postretirement Benefits Schedule of Net Benefit Costs (Table) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 157	$ 146	$ 133
Interest cost	254	266	262
Expected return on plan assets	(429)	(367)	(346)
Amortization of prior service cost (credit)	24	20	18
Amortization of net actuarial loss (gain)	81	97	84
Net periodic benefit cost	87	162	151
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	8	10	10
Interest cost	21	24	25
Amortization of prior service cost (credit)	(22)	(20)	(19)
Amortization of net actuarial loss (gain)	(3)	(4)	(6)
Net periodic benefit cost	$ 4	$ 10	$ 10

Employee Pension and Other Po_5

Employee Pension and Other Postretirement Benefits Schedule of Defined Benefit Plans Discolsures (Table) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year		$ 5,837
Fair value of plan assets at end of year		5,726	$ 5,837
Pension Benefits [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year		6,778	6,050
Service cost		157	146	$ 133
Interest cost		254	266	262
Plan participants' contributions		6	4
Plan amendments			74
Actuarial loss (gain)		(441)	457
Benefits paid		(235)	(219)
Benefit obligation at end of year		6,519	6,778	6,050
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year		5,837	4,911
Actual return on plan assets		(398)	840
Employer contributions		516	301
Plan participants' contributions		6	4
Benefits paid		(235)	(219)
Fair value of plan assets at end of year		5,726	5,837	4,911
Funded status		(793)	(941)
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Pension plan assets	[1]		6
Current liability	[2]	(29)	(25)
Non-current liability	[3]	(764)	(922)
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax [Abstract]
Prior service costs (credits)		99	122
Net actuarial loss (gain)		1,780	1,477
Other Benefits [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year		553	578
Service cost		8	10	10
Interest cost		21	24	25
Plan participants' contributions		8	8
Plan amendments			(10)
Actuarial loss (gain)		(73)	(15)
Benefits paid		(38)	(42)
Benefit obligation at end of year		479	553	$ 578
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Employer contributions		30	34
Plan participants' contributions		8	8
Benefits paid		(38)	(42)
Funded status		(479)	(553)
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Current liability	[2]	(131)	(139)
Non-current liability	[3]	(348)	(414)
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), after Tax [Abstract]
Prior service costs (credits)		(53)	(75)
Net actuarial loss (gain)		$ (88)	$ (18)
[1]	Included in miscellaneous other assets.
[2]	Included in other current liabilities and current portion of postretirement plan liabilities, respectively.
[3]	Included in pension plan liabilities and other postretirement plan liabilities, respectively.

Employee Pension and Other Po_6

Employee Pension and Other Postretirement Benefits Schedule of Amounts in AOCI to be Recongnized (Table) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax [Abstract]
Amortization of prior service cost (credit)	[1]	$ (2)		$ 1
Amortization of net actuarial loss (gain)	[1]	78	$ 93	78
Pension Benefits [Member]
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax [Abstract]
Prior service cost (credit)			(74)
Amortization of prior service cost (credit)		24	20	18
Net actuarial loss (gain)		(386)	16	(241)
Amortization of net actuarial loss (gain)		81	97	84
Other		1	(1)	1
Total changes in accumulated other comprehensive income (loss)		(280)	58	(138)
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Prior service cost (credit)		18
Net loss		113
Total		131
Other Benefits [Member]
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax [Abstract]
Prior service cost (credit)			10
Amortization of prior service cost (credit)		(22)	(20)	(19)
Net actuarial loss (gain)		73	15	(9)
Amortization of net actuarial loss (gain)		(3)	(4)	(6)
Total changes in accumulated other comprehensive income (loss)		48	$ 1	$ (34)
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]
Prior service cost (credit)		(22)
Net loss		(11)
Total		$ (33)
[1]	These accumulated comprehensive loss components are included in the computation of net periodic benefit cost. See Note 17: Employee Pension and Other Postretirement Benefits. The tax expense associated with amounts reclassified from accumulated other comprehensive loss for the years ended December 31, 2018, 2017, and 2016, was $21 million, $36 million, and $27 million, respectively.

Employee Pension and Other Po_7

Employee Pension and Other Postretirement Benefits Schedule of Assumpstions Used and Health Care Cost Trend Rates (Table) (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted Average Assumptions - Benefit Obligation [Abstract]
Initial health care cost trend rate assumed for next year	5.50%	6.00%
Gradually declining to a rate of	4.50%	4.50%
Pension Benefits [Member]
Weighted Average Assumptions - Net Periodic Benefit Cost [Abstract]
Discount rate	3.82%	4.47%	4.73%
Expected long-term rate on plan assets	7.25%	7.25%	7.50%
Rate of compensation increase	3.71%	3.68%	3.66%
Weighted Average Assumptions - Benefit Obligation [Abstract]
Discount rate	4.34%	3.82%
Rate of compensation increase	3.67%	3.71%
Other Benefits [Member]
Weighted Average Assumptions - Net Periodic Benefit Cost [Abstract]
Discount rate	3.85%	4.38%	4.58%
Initial health care cost trend rate assumed for next year	6.00%	6.50%	7.00%
Gradually declining to a rate of	4.50%	5.00%	5.00%
Defined Benefit Plan, Assumptions Used in Calculating Net Periodic Benefit Cost, Health Care Cost Trend Rate, Year ultimate rate is reached	2,025	2,025	2,024
Weighted Average Assumptions - Benefit Obligation [Abstract]
Discount rate	4.33%	3.85%
Initial health care cost trend rate assumed for next year	5.50%	6.00%
Gradually declining to a rate of	4.50%	4.50%
Defined Benefit Plan Health Care Cost Trend Rate, Year ultimate rate is reached	2,024	2,025

Employee Pension and Other Po_8

Employee Pension and Other Postretirement Benefits Schedule of Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates (Table) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)
Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
Effect on postretirement benefit expense - Increase	$ 2
Effect on postretirement benefit expense - Decrease	(2)
Effect on postretirement benefit obligations - Increase	22
Effect on postretirement benefit obligations - Decrease	$ (20)

Employee Pension and Other Po_9

Employee Pension and Other Postretirement Benefits Schedule of Defined Benefit Plans Disclosures, Cash Contributions (Table) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items]
Other benefit plans	$ 30	$ 34	$ 32
Total contributions	546	335	205
Discretionary Contribution [Member] | Qualified [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension contributions	508	294	167
Discretionary Contribution [Member] | Non-qualified [Member]
Defined Benefit Plan Disclosure [Line Items]
Pension contributions	$ 8	$ 7	$ 6

Employee Pension and Other P_10

Employee Pension and Other Postretirement Benefits Schedule of Expected Benefit Payments and Receipts (Table) (Details) $ in Millions	Dec. 31, 2018USD ($)
Pension Benefits [Member]
Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
2,019	$ 254
2,020	266
2,021	285
2,022	306
2,022	326
Years 2024 to 2028	1,927
Other Benefits [Member]
Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
2,019	33
2,020	35
2,021	37
2,022	37
2,022	38
Years 2024 to 2028	181
Defined Benefit Plan, Expected Future Prescription Drug Subsidy Receipt [Abstract]
Years 2024 to 2028	$ 2

Employee Pension and Other P_11

Employee Pension and Other Postretirement Benefits Schedule of Allocation Plan Asset (Table) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 5,726	$ 5,837
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,174	1,270
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,701	1,699
Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,875	2,969
Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		2,851	2,868
U.S. and international equities | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,174	1,270
U.S. and international equities | Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,174	1,270
U.S. and international equities | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[1]	1,910	2,012
Government and agency debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		433	409
Government and agency debt securities | Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		433	409
Corporate and other debt securities | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,265	1,287
Corporate and other debt securities | Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		1,265	1,287
Corporate and other debt securities | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		193	165
Group annuity contract | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3	3
Group annuity contract | Plan assets subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		3	3
Cash and cash equivalents | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	[2]	111	115
Real Estate Investments | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		302	279
Partnership [Member] | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		48	16
Hedge funds | Plan assets not subject to leveling
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		$ 287	$ 281
Minimum | United States Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description		0.15
Minimum | International Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description		0.1
Minimum | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description		0.25
Minimum | Alternative Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description		0.1
Maximum | United States Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description		0.36
Maximum | International Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description		0.29
Maximum | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description		.5
Maximum | Alternative Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment Policy and Strategy, Description		0.25
[1]	U.S. and international equity securities include investments in small, medium, and large capitalization stocks of public companies held in commingled trust funds.
[2]	Cash and cash equivalents are liquid short-term investment funds and include net receivables and payables of the trust. These funds are available for immediate use to fund daily operations, execute investment policies, and serve as a temporary investment vehicle.

Stock Compensation Plans (Narra

Stock Compensation Plans (Narrative) (Details) - $ / shares	3 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years
Restricted performance stock rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation, Arrangement By Share-Based Payment, Stock Awards, Performance Goals, EBITDAP Weight	50.00%	50.00%	50.00%	50.00%
Share-Based Compensation, Arrangement By Share-Based Payment, Stock Awards, Performance Goals, Return on Invested Capital Weight	50.00%	50.00%	50.00%	50.00%
Restricted performance stock rights | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted performance stock rights ultimate vesting percentage	0.00%	0.00%
Restricted performance stock rights | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted performance stock rights ultimate vesting percentage	200.00%	200.00%
Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 174.07	$ 174.07	$ 147.13	$ 113.95	$ 75.73
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period		235,000	387,000	783,000
Share-based Compensation Arrangement by Share-based Payment Award Equity Instruments Other Than Options Transferred From Employees for Minimum Tax Obligations		100,000	200,000	300,000
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted		99,000	109,000	169,000
Stock Rights [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted	10,000
2012 Long Term Incentive Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	3,400,000	3,400,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	4,000,000	4,000,000
2012 Long Term Incentive Stock Plan [Member] | Restricted performance stock rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		100,000	100,000	200,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 261.88	$ 261.88	$ 218.54	$ 134.53
2012 Long Term Incentive Stock Plan [Member] | Restricted stock rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			2 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period		2,900	3,100
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 225.68	$ 225.68	$ 188.13
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	5,100	5,100
2012 Long Term Incentive Stock Plan [Member] | Restricted stock rights | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		2 years
2012 Long Term Incentive Stock Plan [Member] | Restricted stock rights | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years

Stock Compensation Plans Schedu

Stock Compensation Plans Schedule of Status of Stock Awards (Table) (Details) - Stock Awards - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Stock awards, Outstanding, Beginning balance	449	578	891
Stock Awards, Granted	99	109	169
Stock awards, Adjustment due to performance	98	163	326
Stock awards, Vested	(235)	(387)	(783)
Stock awards, Forfeited	(12)	(14)	(25)
Stock awards, Outstanding, Ending balance	399	449	578	891
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]
Stock awards, Outstanding, Weighted Average Grant Date Fair Value, Beginning balance	$ 147.13	$ 113.95	$ 75.73
Stock awards, Granted, Weighted Average Grant Date Fair Value	259.62	217.02	134.78
Stock Awards, Adjustments due to performance, Weighted Average Grant Date Fair Value	142.85	97	46.75
Stock awards, Vested, Weighted Average Grant Date Fair Value	142.85	97	46.75
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	218.50	154.75	127.45
Stock awards, Outstanding, Weighted Average Grant Date Fair Value, Ending balance	$ 174.07	$ 147.13	$ 113.95	$ 75.73
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	8 months	9 months	9 months	7 months

Stock Compensation Plans Stock

Stock Compensation Plans Stock Options (Narrative) (Details) shares in Thousands, $ in Millions	Mar. 31, 2011shares	Dec. 31, 2018	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)shares	Dec. 31, 2015USD ($)shares	Mar. 30, 2011USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Incentive stock plan conversion factor determined in spin-off agreement						1.65
Stock options, Outstanding				262	533
Stock options, Outstanding, Intrinsic Value | $				$ 38	$ 50
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value | $			$ 43	$ 26
Stock Options | 2011 Long Term Incentive Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options issued, number after conversion	1,600
Options fully vested at time of conversion, number						1,400
Stock options, Outstanding, Intrinsic Value | $						$ 15
Stock Options | Granted Prior to 2008 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, Outstanding						1,000
Vesting rate		.25
Vesting period		4 years
Number of years until expiration		10 years
Stock Options | Granted after 2008 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate		.33
Vesting period		3 years
Number of years until expiration		7 years

Stock Compensation Plans Sche_2

Stock Compensation Plans Schedule of Status of Stock Options (Table) (Details) - Stock Options - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Stock options, Outstanding, Beginning balance		262	533
Stock options, Exercised		(262)	(271)
Stock options, Outstanding, Ending balance			262	533
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Stock options, Outstanding, Weighted Average Exercise Price, Beginning balance		$ 37.73	$ 33.90
Stock options, Exercised, Weighted Average Exercise Price		$ 37.73	30.20
Stock options, Outstanding, Weighted Average Exercise Price, Ending balance			$ 37.73	$ 33.90
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Stock options, Weighted Average Remaining Contractual Term			1 month	7 months
Stock Options, Vested, Weighted Average Remaining Contractual Term
Stock options, Outstanding, Intrinsic Value			$ 38	$ 50

Stock Compensation Plans Compen

Stock Compensation Plans Compensation and Unrecognized Compensation Expense (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Compensation expense
Total stock-based compensation expense	$ 36	$ 34	$ 36
Tax benefits recognized for stock-based compensation	8	9	14
Stock Awards
Compensation expense
Realized tax benefits from issuance of stock in settlement of RPSRs and RSRs	16	28	39
Stock Options
Compensation expense
Realized tax benefits from exercise of stock options		$ 17	$ 10
Restricted stock rights
Unrecognized compensation expense
Unrecognized compensation expense associated with stock awards	$ 1
Weighted average period of recognition of unrecognized compensation expense	1 year 4 months
Restricted performance stock rights
Unrecognized compensation expense
Unrecognized compensation expense associated with stock awards	$ 25
Weighted average period of recognition of unrecognized compensation expense	10 months

Unaudited Selected Quarterly _3

Unaudited Selected Quarterly Data (Table) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended												12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017		Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Change in Accounting Estimate [Line Items]
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount													$ (10)	$ 56
Selected Quarterly Financial Information [Abstract]
Sales and service revenues	$ 2,199	$ 2,083	$ 2,020	$ 1,874	$ 1,996		$ 1,863	$ 1,858		$ 1,724			8,176	7,441	$ 7,068
Operating income (loss)	213	290	257	191	231		241	241	[1]	168			951	881	876
Earnings (loss) before income taxes	219	295	262	195	187		220	218	[1]	147			971	772	784
Net earnings (loss)	$ 212	$ 229	$ 239	$ 156	$ 64	[2]	$ 149	$ 147	[1]	$ 119			$ 836	$ 479	$ 573
Dividends declared per share	$ 0.86	$ 0.72	$ 0.72	$ 0.72	$ 0.72		$ 0.60	$ 0.60		$ 0.60	$ 0.60	$ 0.50	$ 3.02	$ 2.52	$ 2.10
Basic earnings (loss) per share	4.96	5.29	5.41	3.48	1.41	[2]	3.28	3.22	[1]	2.57			19.09	10.48	12.24
Diluted earnings (loss) per share	$ 4.94	$ 5.29	$ 5.40	$ 3.48	$ 1.41	[2]	$ 3.27	$ 3.21	[1]	$ 2.56			$ 19.09	$ 10.46	$ 12.14
Ingalls contract [Member]
Change in Accounting Estimate [Line Items]
Increase (decrease) in operating income due to net cumulative catch-up adjustments								$ 30							$ 74
Reduction in income tax rate [Member]
Change in Accounting Estimate [Line Items]
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount					$ 56								$ (10)	$ 56
[1]	(1) In the second quarter of 2017, the Company recorded a $30 million favorable cumulative adjustment on a contract at the Ingalls segment.
[2]	(2) In the fourth quarter of 2017, the Tax Act resulted in an increase of $56 million to the Company's income tax expense.

Subsidiary Guarantors (Narrativ

Subsidiary Guarantors (Narrative) (Details)	12 Months Ended
	Dec. 31, 2018
Subsidiary Guarantors [Abstract]
Parent ownership percentage of subsidiary guarantors	100.00%

Valuation and Qualifying Accoun

Valuation and Qualifying Accounts (Details) - SEC Schedule, 12-09, Valuation Allowance, Deferred Tax Asset [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation allowances beginning balance	$ 12	$ 11	$ 11
(Benefits)/Charges to Income	0	1	0
Other	0	0	0
Valuation allowances ending balance	$ 12	$ 12	$ 11