INFORMATION ON BUSINESS SEGMENTS - FAS/CAS Pension Adjustment (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 25, 2018	Mar. 26, 2017
Segment Reporting Information [Line Items]
Non-operating FAS pension expense	$ (199)	$ (186)
Net FAS/CAS pension adjustment	252	217
Segment reconciling items
Segment Reporting Information [Line Items]
FAS pension expense/service cost	(157)	(159)
Less: CAS pension cost	608	562
FAS/CAS operating adjustment	451	403
Qualified defined benefit pension plans
Segment Reporting Information [Line Items]
FAS pension expense/service cost	356	345
Qualified defined benefit pension plans \| Qualified Plan
Segment Reporting Information [Line Items]
FAS pension expense/service cost	$ (356)	$ (345)

Fas Cas Operating Adjustment

No definition available.

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- Definition

This item represents the difference between pension expense calculated for financial reporting purposes under GAAP and pension costs calculated and funded in accordance with U.S. Government Cost Accounting Standards (CAS).

+ References

No definition available.

+ Details

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- Definition

Financial Accounting Standards, Non-Operating Pension Expense

+ References

No definition available.

+ Details

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- Definition

Pension expense calculated under U.S. Government Cost Accounting Standards.

+ References

No definition available.

+ Details

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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- Definition

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.

+ References

No definition available.

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