Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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The amount of inventory recognized as of the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Acquisitions - AllianceRx Walgreens Prime (Details) - USD ($) $ in Millions		12 Months Ended
	Mar. 31, 2017	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2015
Business Acquisition [Line Items]
Goodwill		$ 15,632	$ 15,527	$ 16,372
AllianceRx Walgreens Prime
Business Acquisition [Line Items]
Total consideration	$ 720
Accounts receivable	217
Inventories	149
Property, plant and equipment	11
Intangible assets	331
Trade accounts payable, accrued expenses and other liabilities	(91)
Total identifiable net assets	617
Goodwill	$ 103
Professional fees		$ 14
Customer Contracts \| AllianceRx Walgreens Prime
Business Acquisition [Line Items]
Weighted average useful life	15 years