Related Party Transactions (Details) - Walgreens Boots Alliance, Inc. - Investor - USD ($) $ in Billions	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Related Party Transaction [Line Items]
Revenue from related party	$ 15.3	$ 12.7
Receivable from related party	$ 6.1		$ 5.6
AmerisourceBergen
Related Party Transaction [Line Items]
Ownership percentage (more than)	10.00%

For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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