Goodwill and Identifiable Intangible Assets - Changes in Goodwill by Segment (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Balance, Beginning	$ 7,796us-gaap_Goodwill	$ 7,776us-gaap_Goodwill
Business acquisitions	36us-gaap_GoodwillAcquiredDuringPeriod	44us-gaap_GoodwillAcquiredDuringPeriod
Business disposition	(1)	(2)
Foreign currency translation adjustments	(99)	(22)
Assets held for sale	(231)
Balance, Ending	7,501us-gaap_Goodwill	7,796us-gaap_Goodwill
Electronic Systems [Member]
Goodwill [Line Items]
Balance, Beginning	4,085	4,046
Business acquisitions	(3)	44
Business disposition	(1)	(2)
Foreign currency translation adjustments	(77)	(3)
Assets held for sale	(231)
Balance, Ending	3,773	4,085
Aerospace Systems [Member]
Goodwill [Line Items]
Balance, Beginning	1,751	1,770
Business acquisitions
Business disposition
Foreign currency translation adjustments	(21)	(19)
Assets held for sale
Balance, Ending	1,730	1,751
Communication Systems [Member]
Goodwill [Line Items]
Balance, Beginning	992	992
Business acquisitions
Business disposition
Foreign currency translation adjustments
Assets held for sale
Balance, Ending	992	992
NSS [Member]
Goodwill [Line Items]
Balance, Beginning	968	968
Business acquisitions	39
Business disposition
Foreign currency translation adjustments	(1)
Assets held for sale
Balance, Ending	$ 1,006	$ 968

Goodwill Allocated To Assets Held For Sale Or Sold

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

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- Definition

Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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