Special Charges - Restructuring reserve activity and total expected cash outlay (Details) $ in Millions	9 Months Ended
Sep. 29, 2018 USD ($)
Special Charges
Remaining expected cash payments for restructuring activities	$ 20
Restructuring reserve activity
Balance at beginning of period	44
Cash paid	(25)
Provision for 2016 Plan	3
Reversals	(2)
Balance at end of period	20
Severance Costs
Restructuring reserve activity
Balance at beginning of period	24
Cash paid	(18)
Reversals	(2)
Balance at end of period	4
Contract Terminations and Other
Restructuring reserve activity
Balance at beginning of period	20
Cash paid	(7)
Provision for 2016 Plan	3
Balance at end of period	$ 16

Represents the remaining amount of expected cash payments for the restructuring activities.

No definition available.

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- Definition

Amount of restructuring reserve reversals associated with the exit or disposal activities.

+ References

No definition available.

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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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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
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-Publisher FASB
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-Section 45
-Paragraph 17
-Subparagraph (f)
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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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