Segment Information (Unaudited) (Details 1) $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($) segment	Mar. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	3
Sales	$ 5,956	$ 5,957
Operating income	739	780
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income	701	735
Operating Segments [Member] \| Aerospace Systems [Member]
Segment Reporting Information [Line Items]
Sales	2,574	2,498
Operating income	286	312
Operating Segments [Member] \| Mission Systems [Member] [Member]
Segment Reporting Information [Line Items]
Sales	2,693	2,711
Operating income	353	344
Operating Segments [Member] \| Technology Services [Member]
Segment Reporting Information [Line Items]
Sales	1,214	1,267
Operating income	126	133
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Sales	525	519
Operating income	64	54
Net FAS/CAS pension adjustment Income (Expense) [Member]
Segment Reporting Information [Line Items]
Operating income	74	83
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Operating income	(33)	(38)
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Operating income	$ (3)	$ 0

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The net result for the period of deducting operating expenses from operating revenues.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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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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