| **PENSION AND OTHER POSTRETIREMENT BENEFITS - Funded Status of Defined Benefit Plans (Details) - USD ($) $ in Millions** | Jun. 29, 2018 | Jun. 30, 2017 | Jul. 01, 2016 |
|--------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|
| **Defined Benefit Plan Disclosure [Line Items]**                                                                         |          |          |          |
| Fair value of plan assets                                                                                                | $ 5,305       | $ 5,133       | $ 4,489       |
| Projected benefit obligation                                                                                             | (6,007)       | (6,405)       | (6,782)       |
| Funded status                                                                                                            | (702)         | (1,272)       |          |
| Other non-current assets                                                                                                 |          |          |          |
| **Consolidated Balance Sheet line item amounts:**                                                                        |          |          |          |
| Other non-current assets                                                                                                 | 15            | 9             |          |
| Compensation and benefits                                                                                                |          |          |          |
| **Consolidated Balance Sheet line item amounts:**                                                                        |          |          |          |
| Compensation and benefits                                                                                                | (3)           | (3)           |          |
| Defined benefit plans                                                                                                    |          |          |          |
| **Consolidated Balance Sheet line item amounts:**                                                                        |          |          |          |
| Defined benefit plans                                                                                                    | (714)         | (1,278)       |          |
| Pension                                                                                                                  |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                         |          |          |          |
| Fair value of plan assets                                                                                                | 5,098         | 4,921         | 4,273         |
| Projected benefit obligation                                                                                             | (5,774)       | (6,140)       | (6,471)       |
| Funded status                                                                                                            | (676)         | (1,219)       |          |
| Pension | Other non-current assets                                                                                       |          |          |          |
| **Consolidated Balance Sheet line item amounts:**                                                                        |          |          |          |
| Other non-current assets                                                                                                 | 15            | 9             |          |
| Pension | Compensation and benefits                                                                                      |          |          |          |
| **Consolidated Balance Sheet line item amounts:**                                                                        |          |          |          |
| Compensation and benefits                                                                                                | (2)           | (2)           |          |
| Pension | Defined benefit plans                                                                                          |          |          |          |
| **Consolidated Balance Sheet line item amounts:**                                                                        |          |          |          |
| Defined benefit plans                                                                                                    | (689)         | (1,226)       |          |
| Other Benefits                                                                                                           |          |          |          |
| **Defined Benefit Plan Disclosure [Line Items]**                                                                         |          |          |          |
| Fair value of plan assets                                                                                                | 207           | 212           | 216           |
| Projected benefit obligation                                                                                             | (233)         | (265)         | $ (311)       |
| Funded status                                                                                                            | (26)          | (53)          |          |
| Other Benefits | Other non-current assets                                                                                |          |          |          |
| **Consolidated Balance Sheet line item amounts:**                                                                        |          |          |          |
| Other non-current assets                                                                                                 | 0             | 0             |          |
| Other Benefits | Compensation and benefits                                                                               |          |          |          |
| **Consolidated Balance Sheet line item amounts:**                                                                        |          |          |          |
| Compensation and benefits                                                                                                | (1)           | (1)           |          |
| Other Benefits | Defined benefit plans                                                                                   |          |          |          |
| **Consolidated Balance Sheet line item amounts:**                                                                        |          |          |          |
| Defined benefit plans                                                                                                    | $ (25)        | $ (52)        |          |

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| - Definition
Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.
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| - Definition
Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.
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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.
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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.
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| - Definition
Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.
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| - Definition
Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current.
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| - Definition
Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.
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