Debt and Credit Agreements - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 30, 2016
Debt Instrument [Line Items]
Subtotal Long-term Debt (including current portion)	$ 11,809	$ 11,293
Less Debt Due within One Year	(19)	(331)
Long-term Debt (excluding current portion)	$ 11,790	10,962
Notes
Debt Instrument [Line Items]
Average Interest Rates (as a percent)	4.30%
Subtotal Long-term Debt (including current portion)	$ 11,591	11,055
Equipment Obligations
Debt Instrument [Line Items]
Average Interest Rates (as a percent)	6.30%
Subtotal Long-term Debt (including current portion)	$ 213	232
Capital Leases
Debt Instrument [Line Items]
Average Interest Rates (as a percent)	16.20%
Subtotal Long-term Debt (including current portion)	$ 5	$ 6

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
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The average effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
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