Debt and Credit Agreements - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 30, 2016	Dec. 25, 2015
Debt Instrument [Line Items]
Subtotal Long-term Debt (including current portion)	$ 11,293	$ 10,535
Less Debt Due within One Year	(331)	(20)
Long-term Debt (excluding current portion)	$ 10,962	10,515
Notes
Debt Instrument [Line Items]
Average Interest Rates (as a percent)	4.50%
Subtotal Long-term Debt (including current portion)	$ 11,055	10,277
Equipment Obligations
Debt Instrument [Line Items]
Average Interest Rates (as a percent)	6.30%
Subtotal Long-term Debt (including current portion)	$ 232	250
Capital Leases
Debt Instrument [Line Items]
Average Interest Rates (as a percent)	15.60%
Subtotal Long-term Debt (including current portion)	$ 6	7
Convertible Debentures
Debt Instrument [Line Items]
Average Interest Rates (as a percent)	1.00%
Subtotal Long-term Debt (including current portion)	$ 0	1
Adjustments for New Accounting Pronouncement [Member] \| Other Noncurrent Assets [Member]
Debt Instrument [Line Items]
Subtotal Long-term Debt (including current portion)		$ (168)

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
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-Section S99
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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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No definition available.

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