| **Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - Fair Value - Fair Value, Measurements, Recurring - USD ($) $ in Millions** | Sep. 29, 2017 | Jun. 30, 2017 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Assets**                                                                                                                                                              |          |          |
| Fair value of plan assets                                                                                                                                               | $ 123         | $ 112         |
| Investments Measured at NAV, assets                                                                                                                                     | 74            | 75            |
| **Liabilities**                                                                                                                                                         |          |          |
| Fair value of plan liabilities                                                                                                                                          | 142           | 126           |
| Equity securities and mutual funds                                                                                                                                      |          |          |
| **Liabilities**                                                                                                                                                         |          |          |
| Fair value of plan liabilities                                                                                                                                          | 56            | 46            |
| Common/collective trusts and guaranteed investment contracts                                                                                                            |          |          |
| **Liabilities**                                                                                                                                                         |          |          |
| Investments Measured at NAV, liabilities                                                                                                                                | 86            | 80            |
| Equity security                                                                                                                                                         |          |          |
| **Assets**                                                                                                                                                              |          |          |
| Fair value of plan assets                                                                                                                                               | 49            | 37            |
| Corporate-owned life insurance                                                                                                                                          |          |          |
| **Assets**                                                                                                                                                              |          |          |
| Investments Measured at NAV, assets                                                                                                                                     | 25            | 25            |
| Equity fund                                                                                                                                                             |          |          |
| **Assets**                                                                                                                                                              |          |          |
| Investments Measured at NAV, assets                                                                                                                                     | 49            | 50            |
| Level 1 | Equity securities and mutual funds                                                                                                                            |          |          |
| **Liabilities**                                                                                                                                                         |          |          |
| Fair value of plan liabilities                                                                                                                                          | 56            | 46            |
| Level 1 | Equity security                                                                                                                                               |          |          |
| **Assets**                                                                                                                                                              |          |          |
| Fair value of plan assets                                                                                                                                               | $ 49          | $ 37          |

| X                                                                                                                                                                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Alternative Investment, Fair Value Disclosure Liability
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Defined Benefit Plan, Fair Value of Plan Liabilities
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value of investment in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. Excludes measurement of net asset value as estimate of fair value.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=SL6742756-110258
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| X                                                                                                                                                                                                           |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.
+ 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 (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920
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| X                                                                                                                                                                                                                |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
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| X                                                                                                                                                                                    |
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| X                                                                                                                                                                      |
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| X                                                                                                                                                        |
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| X                                                                                                                                                               |
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| X                                                                                                                                                   |
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