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Pensions and Other Post-retirement Benefit Plans Defined Benefit Pension Plans' Major Asset Categories and Their Associated Fair Values (Details) - USD ($) $ in Millions | Jun. 29, 2018 | Jun. 30, 2017
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets |  | $ 200 | $ 189
Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets |  | 3 | 2
Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets |  | 197 | 187
Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets |  | 0 | 0
Equity Commingled/Mutual Funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | [1],[2] | 68 | 67
Equity Commingled/Mutual Funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | [1],[2] | 0 | 0
Equity Commingled/Mutual Funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | [1],[2] | 68 | 67
Equity Commingled/Mutual Funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | [1],[2] | 0 | 0
Fixed income commingled/mutual funds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | [1],[3] | 125 | 116
Fixed income commingled/mutual funds | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | [1],[3] | 0 | 0
Fixed income commingled/mutual funds | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | [1],[3] | 125 | 116
Fixed income commingled/mutual funds | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets | [1],[3] | 0 | 0
Cash equivalents and short-term investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets |  | 7 | 6
Cash equivalents and short-term investments | Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets |  | 3 | 2
Cash equivalents and short-term investments | Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets |  | 4 | 4
Cash equivalents and short-term investments | Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined benefit plan, fair value of plan assets |  | $ 0 | $ 0
[1] | Commingled funds represent pooled institutional investments.
[2] | Equity mutual funds invest primarily in equity securities.
[3] | Fixed income mutual funds invest primarily in fixed income securities.

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- 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 + Details
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