Other - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
Jun. 25, 2017	Mar. 26, 2017	Jun. 26, 2016	Jun. 25, 2017	Jun. 26, 2016
Additional charge to costs		$ 120
Additional charge to costs, after tax		$ 74
Additional charge to costs, per share		$ 0.25
Cumulative losses including reserves				$ 260
Increase in operating profit due to profit rate adjustments	$ 485		$ 355	775	$ 715
Increase in net earnings due to profit rate adjustments	$ 315		$ 231	$ 504	$ 465
Increase in diluted earnings per common share due to profit rate adjustments	$ 1.08		$ 0.75	$ 1.73	$ 1.51
Effective income tax rate	28.80%		25.70%	26.40%	22.60%
A2100
Development expense				$ 90
Estimated cumulative losses	$ 260			$ 260

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Estimated cumulative losses including reserves.

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Increase (decrease) in net earnings due to favorable/unfavorable profit rate adjustments.

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Increase (decrease) in diluted earnings per share due to favorable/unfavorable profit rate adjustments.

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Increase (decrease) in operating profit due to favorable/unfavorable profit rate adjustments.

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Valuation allowances and reserves charged to cost and expense earnings per share.

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Valuation allowances and reserves charged to cost and expense, net of tax.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

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Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

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