Goodwill and Other Purchased Intangible Assets.

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The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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Aggregate amount of intangible asset amortization recognized as expense during the period.

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Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The calculated weighted-average useful life of all finite-lived intangible assets.

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-Name Accounting Standards Codification

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The amount of amortization expense expected to be recognized during the remainder of the current fiscal year.

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The amount of amortization expense expected to be recognized during year five of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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The accumulated impairment losses related to goodwill as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Goodwill and Other Purchased Intangible Assets (Details) (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011 Year	Sep. 30, 2010	Dec. 31, 2010
Goodwill (Table Amounts)
Goodwill	$ 12,376		$ 12,376		$ 12,376
Goodwill (Amounts in Paragraph)
Accumulated goodwill impairment losses	570		570		570
Purchased Intangible Assets (Table Amounts) [Abstract]
Gross Carrying Amount	1,805		1,805		1,805
Accumulated Amortization	(1,641)		(1,641)		(1,613)
Net Carrying Amount	164		164		192
Expected amortization for the year ending December 31 (Table Amounts) [Abstract]
2011 (October 1 - December 31)			9
2012			36
2013			29
2014			16
2015			15
2016			11
Additional disclosure on Goodwill and Other Intangible Assets (Amounts in Paragraphs)
Weighted-average useful life for purchased intangible assets			18
Aggregate amortization expense	10	17	28	53
Aerospace Systems
Goodwill (Table Amounts)
Goodwill	3,801		3,801		3,801
Electronic Systems
Goodwill (Table Amounts)
Goodwill	2,402		2,402		2,402
Information Systems
Goodwill (Table Amounts)
Goodwill	5,248		5,248		5,248
Technical Services
Goodwill (Table Amounts)
Goodwill	925		925		925
Contract and Program Intangibles
Purchased Intangible Assets (Table Amounts) [Abstract]
Gross Carrying Amount	1,705		1,705		1,705
Accumulated Amortization	(1,554)		(1,554)		(1,531)
Net Carrying Amount	151		151		174
Other Purchased Intangibles
Purchased Intangible Assets (Table Amounts) [Abstract]
Gross Carrying Amount	100		100		100
Accumulated Amortization	(87)		(87)		(82)
Net Carrying Amount	$ 13		$ 13		$ 18