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Pension and Other Post-Retirement Benefit Plans - Defined Benefit Pension Plans' Major Asset Categories and Their Associated Fair Values (Details) - USD ($) $ in Millions | Jun. 27, 2025 | Jun. 28, 2024
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Equity commingled/mutual funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | $ 66 | $ 58
Equity commingled/mutual funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 0 | 0
Equity commingled/mutual funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 66 | 58
Equity commingled/mutual funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 0 | 0
Fixed income commingled/mutual funds |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 110 | 99
Fixed income commingled/mutual funds | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 0 | 0
Fixed income commingled/mutual funds | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 110 | 99
Fixed income commingled/mutual funds | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 0 | 0
Net plan assets subject to leveling | Total |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 176 | 157
Net plan assets subject to leveling | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 0 | 0
Net plan assets subject to leveling | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 176 | 157
Net plan assets subject to leveling | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 0 | 0
Real estate investment trust at net asset value | Net asset value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 28 | 27
Total investments at fair value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 204 | 184
Total investments at fair value | Level 1 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 0 | 0
Total investments at fair value | Level 2 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | 176 | 157
Total investments at fair value | Level 3 |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets measured at fair value: | $ 0 | $ 0

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