Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.10)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(4))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
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-Section S99
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
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-Section S99
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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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No definition available.

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Summary of Significant Accounting Policies Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Other Non-current Assets	$ 159		$ 163
Accounts Receivable, Net of Allowance for Uncollectible Accounts of $156 in 2017 and $129 in 2016	1,103		$ 1,383
Revenue Recognition [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Cumulative Effect of Change in Accounting Estimate		$ 31
Interest Income (Expense), Net		4
Accounts Receivable, Net, Current		27
VENEZUELA \| Revenue Recognition [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Cumulative Effect of Change in Accounting Estimate	230
Other Non-current Assets	158
Accounts Receivable, Net of Allowance for Uncollectible Accounts of $156 in 2017 and $129 in 2016	$ 72
Other Noncurrent Assets [Member] \| VENEZUELA
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Accounts Receivable, Net of Allowance for Uncollectible Accounts of $156 in 2017 and $129 in 2016		$ 158