Long-Term Debt (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Dec. 29, 2017	Jun. 30, 2017
Debt Instrument [Line Items]
Total debt	$ 3,910	$ 3,945
Plus: unamortized bond premium	27	29
Less: unamortized discounts and issuance costs	(23)	(24)
Total debt, net	3,914	3,950
Less: current portion of long-term debt	(523)	(554)
Total long-term debt, net	3,391	3,396
Variable-rate debt
Debt Instrument [Line Items]
Total debt	270	305
Variable-rate debt \| Term loan, 3-year tranche, due May 29, 2018
Debt Instrument [Line Items]
Total debt	$ 20	$ 36
Debt instrument term	3 years	3 years
Variable-rate debt \| Term loan, 5-year tranche, due May 29, 2020
Debt Instrument [Line Items]
Total debt	$ 0	$ 269
Debt instrument term	5 years	5 years
Variable-rate debt \| Floating rate notes, due April 30, 2020
Debt Instrument [Line Items]
Total debt	$ 250	$ 0
Fixed-rate debt
Debt Instrument [Line Items]
Total debt	3,640	3,640
Fixed-rate debt \| 1.999% notes, due April 27, 2018
Debt Instrument [Line Items]
Total debt	$ 500	$ 500
Interest rate on fixed rate debt (percent)	1.999%	1.999%
Fixed-rate debt \| 2.7% notes, due April 27, 2020
Debt Instrument [Line Items]
Total debt	$ 400	$ 400
Interest rate on fixed rate debt (percent)	2.70%	2.70%
Fixed-rate debt \| 4.4% notes, due December 15, 2020
Debt Instrument [Line Items]
Total debt	$ 400	$ 400
Interest rate on fixed rate debt (percent)	4.40%	4.40%
Fixed-rate debt \| 5.55% notes, due October 1, 2021
Debt Instrument [Line Items]
Total debt	$ 400	$ 400
Interest rate on fixed rate debt (percent)	5.55%	5.55%
Fixed-rate debt \| 3.832% notes, due April 27, 2025
Debt Instrument [Line Items]
Total debt	$ 600	$ 600
Interest rate on fixed rate debt (percent)	3.832%	3.832%
Fixed-rate debt \| 7.0% debentures, due January 15, 2026
Debt Instrument [Line Items]
Total debt	$ 100	$ 100
Interest rate on fixed rate debt (percent)	7.00%	7.00%
Fixed-rate debt \| 6.35% debentures, due February 1, 2028
Debt Instrument [Line Items]
Total debt	$ 26	$ 26
Interest rate on fixed rate debt (percent)	6.35%	6.35%
Fixed-rate debt \| 4.854% notes, due April 27, 2035
Debt Instrument [Line Items]
Total debt	$ 400	$ 400
Interest rate on fixed rate debt (percent)	4.854%	4.854%
Fixed-rate debt \| 6.15% notes, due December 15, 2040
Debt Instrument [Line Items]
Total debt	$ 300	$ 300
Interest rate on fixed rate debt (percent)	6.15%	6.15%
Fixed-rate debt \| 5.054% notes, due April 27, 2045
Debt Instrument [Line Items]
Total debt	$ 500	$ 500
Interest rate on fixed rate debt (percent)	5.054%	5.054%
Other
Debt Instrument [Line Items]
Total debt	$ 14	$ 14

Debt Instrument, Unamortized Discount and Debt Issuance Costs, Net

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Contractual interest rate for funds borrowed, under the debt agreement.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Amount, after accumulated amortization, of debt premium.

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-SubTopic 30
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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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