Summary Of Significant Accounting Policies - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2013 Segment	Dec. 31, 2012	Dec. 31, 2011
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Number of business groups	4
Net increase in operating earnings from the impact of revisions in contract	$ 351	$ 180	$ 356
Net increase in operating earnings per share from the quarterly impact of revisions in contract	$ 0.65	$ 0.33	$ 0.63
Discontinued operations, net of tax	(129)	0	(26)
Termination Of A - 12 Program [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Cash cost, after-tax	129
Loss Contingency, Settlement Agreement, Consideration	$ 198
Loss Contingency, Range of Possible Loss	57

Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 29

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

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-Section 03

-Paragraph 15

-Article 5

+ Details

- Definition

Describes the estimated range of loss from the specified contingency when no single amount within the range appears to be a better estimate than any other amount within the range, may disclose the factors that could cause the estimate to change, and may indicate that a material change in estimate might occur based on a reasonably possible change in circumstances.

+ References

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+ Details