Available-for-Sale Securities (Schedule of Available-for-Sale Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Jun. 30, 2016
Schedule of Available-for-sale Securities [Line Items]
Total current available-for-sale securities	$ 110	$ 113
Total long-term available-for-sale securities	91	87
Total available-for-sale securities		200
Treasury bills
Schedule of Available-for-sale Securities [Line Items]
Total current available-for-sale securities	0	3
Total long-term available-for-sale securities	24	10
International bonds
Schedule of Available-for-sale Securities [Line Items]
Total current available-for-sale securities	3	2
Total long-term available-for-sale securities	3	1
Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Total current available-for-sale securities	59	58
Total long-term available-for-sale securities	29	36
U.S. agency bonds
Schedule of Available-for-sale Securities [Line Items]
Total current available-for-sale securities	11	6
Total long-term available-for-sale securities	0	9
Asset-backed securities
Schedule of Available-for-sale Securities [Line Items]
Total current available-for-sale securities	26	28
Total long-term available-for-sale securities	16	17
International equity securities
Schedule of Available-for-sale Securities [Line Items]
Total current available-for-sale securities	1	2
U.S. agency mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Total current available-for-sale securities	10	14
Total long-term available-for-sale securities	$ 19	$ 14

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

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Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Available-for-Sale Securities
-URI http://asc.fasb.org/extlink&oid=6505594

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26626-111562

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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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