| **PENSION AND OTHER POSTRETIREMENT BENEFITS - Fair Value of Plan Assets (Details) - USD ($) $ in Millions** | Jun. 28, 2019 | Jun. 29, 2018 | Jun. 30, 2017 |
|-------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | $ 5,159       | $ 5,305       | $ 5,133       |
| Receivables (payables), net                                                                                 | 84            | (4)           |          |
| Domestic equities                                                                                           |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 1,173         | 1,221         |          |
| International equities                                                                                      |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 896           | 903           |          |
| Corporate bonds                                                                                             |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 923           | 811           |          |
| Government securities                                                                                       |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 332           | 335           |          |
| Other                                                                                                       |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 2             | 2             |          |
| Cash and cash equivalents                                                                                   |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 59            | 209           |          |
| Total                                                                                                       |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 3,385         | 3,481         |          |
| Level 1                                                                                                     |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 2,081         | 2,094         |          |
| Level 1 | Domestic equities                                                                                 |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 1,173         | 1,189         |          |
| Level 1 | International equities                                                                            |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 896           | 899           |          |
| Level 1 | Corporate bonds                                                                                   |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 0             |          |
| Level 1 | Government securities                                                                             |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 0             |          |
| Level 1 | Other                                                                                             |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 0             |          |
| Level 1 | Cash and cash equivalents                                                                         |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 12            | 6             |          |
| Level 2                                                                                                     |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 1,285         | 1,374         |          |
| Level 2 | Domestic equities                                                                                 |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 32            |          |
| Level 2 | International equities                                                                            |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 4             |          |
| Level 2 | Corporate bonds                                                                                   |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 906           | 800           |          |
| Level 2 | Government securities                                                                             |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 332           | 335           |          |
| Level 2 | Other                                                                                             |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 0             |          |
| Level 2 | Cash and cash equivalents                                                                         |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 47            | 203           |          |
| Level 3                                                                                                     |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 19            | 13            | 2             |
| Level 3 | Domestic equities                                                                                 |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 0             |          |
| Level 3 | International equities                                                                            |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 0             |          |
| Level 3 | Corporate bonds                                                                                   |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 17            | 11            |          |
| Level 3 | Government securities                                                                             |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 0             |          |
| Level 3 | Other                                                                                             |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 2             | 2             | 2             |
| Level 3 | Cash and cash equivalents                                                                         |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 0             | 0             |          |
| Level 3 | Fixed income funds                                                                                |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 17            | 11            | $ 0           |
| Investments Measured at NAV                                                                                 |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 1,690         | 1,828         |          |
| Investments Measured at NAV | Equity funds                                                                  |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 703           | 714           |          |
| Investments Measured at NAV | Fixed income funds                                                            |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 362           | 318           |          |
| Investments Measured at NAV | Hedge funds                                                                   |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | 331           | 395           |          |
| Investments Measured at NAV | Private equity funds                                                          |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                            |          |          |          |
| Total fair value of plan assets                                                                             | $ 294         | $ 401         |          |

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| - 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 asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.
+ References
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