Stock Compensation Plans (Details 4) (Unaudited) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Mar. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option conversion ratio			1.09
Shares issued and counted against remaining shares available	4.5
Compensation Expense [Abstract]
Total pre-tax stock-based compensation expense	$ 64	$ 69
Unrecognized compensation expense related to unvested awards	216
Weighted-average period for unrecognized compensation expense to be charged to expense (years)	1.5
Stock Option Plan
Compensation Expense [Abstract]
Total pre-tax stock-based compensation expense	7	18
Tax benefits recognized in the condensed consolidated statements of operations for stock-based compensation	26	27
Realized tax benefits from exercise of stock options	15	11
Unrecognized compensation expense related to unvested awards	20
Stock Option And Awards Plans [Abstract]
Vesting period of stock options and stock awards (years)	3 to 4 years
Expected option life for executives (years)	6 years
Expected option life for non-executives (years)	5 years
Weighted-average grant date fair value of stock options granted	$ 14	$ 11
Total intrinsic value of options exercised	38	28
Stock Awards Plan
Compensation Expense [Abstract]
Total pre-tax stock-based compensation expense	57	51
Realized tax benefits from issuance of stock awards	32	34
Unrecognized compensation expense related to unvested awards	196
Stock Option And Awards Plans [Abstract]
Vesting period of stock options and stock awards (years)	3 years
Fair value of common stock issued - grant date	101	91
Fair value of common stock issued - issuance date	87	76
Common stock issued to employees in settlement of prior year stock awards that were fully vested	1,400,000	1,300,000
Weighted-average grant date fair value - granted	$ 63	$ 60
Stock awards - granted	1,617,000	2,200,000
Spin Off Of Hii
Compensation Expense [Abstract]
Amount recorded in discontinued operations of the stock-based compensation	$ 3	$ 7
2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares issued or transferred pursuant to awards	39,100,000
2001 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares issued or transferred pursuant to awards	17,100,000

Disclosure of the aggregate tax benefit realized from the issuance of stock awards.

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The period of time a share-based award, for executives, is expected to be outstanding. A share-based award's expected term shall be determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. An entity is required to aggregate individual awards into relatively homogeneous groups.

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The period of time a share-based award, for non-executives, is expected to be outstanding. A share-based award's expected term shall be determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. An entity is required to aggregate individual awards into relatively homogeneous groups.

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Stock option conversion ratio.

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Stock based compensation recorded in discontinued operations related to spin off of shipbuilding business.

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The fair value, at the time of grant, for shares issued during the reporting period as a result of any share-based compensation plan other than an employee stock ownership plan (ESOP).

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The fair value, at the time of issuance, of shares issued during the reporting period as a result of any share-based compensation plan other than an employee stock ownership plan (ESOP).

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Stock Option And Awards Plans.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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