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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 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section H

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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-Number 210
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Debt (Schedule Of Outstanding Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Mar. 31, 2015
Debt Instrument [Line Items]
Current portion of long-term debt	$ 13	$ 12
Short-term debt	265	12
Long-term debt, current and noncurrent	4,761	4,414
Long-term debt	4,748	4,402
2.30% Senior Debt Obligations Due 2017
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 250	249
Interest rate	2.30%
2.55% Senior Debt Obligations Due 2018
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 249	249
Interest rate	2.55%
2.35% Senior Debt Obligations Due 2019
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 298	298
Interest rate	2.35%
2.35% Senior Debt Obligations Due 2020
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 497	496
Interest rate	2.35%			2.35%
4.80% Senior Debt Obligations Due 2021
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 498	497
Interest rate	4.80%
3.30% Senior Debt Obligations Due 2023
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 347	0
Interest rate	3.30%
4.05% Senior Debt Obligations Due 2023
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 248	248
Interest rate	4.05%
3.50% Senior Debt Obligations Due 2024
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 595	595
Interest rate	3.50%
3.50% Senior Debt Obligations Due 2025
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 495	495
Interest rate	3.50%
3.75% Senior Debt Obligations Due 2026
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 595	595
Interest rate	3.75%		3.75%
5.875% Senior Debt Obligations Due 2033
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 297	297
Interest rate	5.875%
Mortgage Due 2035
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 390	393
Interest rate	5.70%
Other
Debt Instrument [Line Items]
Long-term debt, current and noncurrent	$ 2	2
Commercial Paper
Debt Instrument [Line Items]
Commercial paper outstanding	$ 252	$ 0