Available-for-Sale Investments (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
Mar. 18, 2016	Aug. 31, 2016	Aug. 31, 2015
Summary of cost and fair value of available-for-sale securities [Abstract]
Amortized cost basis			$ 754
Gross unrealized gains			430
Gross unrealized (losses)			(1)
Fair value			1,183
Available for sale securities, current		$ 32	36
AmerisourceBergen Common Stock [Member]
Summary of cost and fair value of available-for-sale securities [Abstract]
Amortized cost basis			717
Gross unrealized gains			430
Gross unrealized (losses)			0
Fair value			1,147
Warrant to purchase common stock (in shares)	22,696,912
Warrant exercise price (in dollars per share)	$ 51.50
Gain from reclassification of income from other comprehensive income to other income (expense)	$ 268
Sale of acquired available-for-sale securities		7	52
Corporate Bonds and Treasury Bills [Member]
Summary of cost and fair value of available-for-sale securities [Abstract]
Amortized cost basis		30	37
Gross unrealized gains		2	0
Gross unrealized (losses)		0	(1)
Fair value		$ 32	$ 36

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in equity securities classified as available-for-sale.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

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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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Amount of equity securities categorized neither as held-to-maturity nor as trading.

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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

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-Publisher FASB
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-Publisher FASB
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-Section 50
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Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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-Subparagraph (d)
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The aggregate value of securities held, which were categorized neither as trading nor held-to-maturity, for which the interest rate reset through an auction process, that failed to be liquidated through auction, and which were sold during the period.

+ References

No definition available.

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