Segment Information (Revenue by Reportable Segment) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended									12 Months Ended
	Jun. 30, 2014		Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2012
Segment Reporting Information
Revenue	$ 22,894	[1]	$ 21,427	$ 22,240	$ 24,523	$ 25,420	$ 24,552	$ 25,232	$ 25,889	$ 91,084		$ 101,093		$ 107,552
Pharmaceutical
Segment Reporting Information
Revenue										80,110	[2]	91,097	[2]	97,925	[2]
Medical
Segment Reporting Information
Revenue										10,962		10,060		9,642
Reportable Segments
Segment Reporting Information
Revenue										91,072		101,157		107,567
Corporate
Segment Reporting Information
Revenue										$ 12	[3]	$ (64)	[3]	$ (15)	[3]
Walgreens Co | Pharmaceutical
Segment Reporting Information
Contract expiration date										Aug. 31, 2013
Express Scripts, Inc. | Pharmaceutical
Segment Reporting Information
Contract expiration date												Sep. 30, 2012

[1] During the fourth quarter of fiscal 2014, we recorded an out-of-period decrease in revenue of $14 million related to customer pricing adjustments, of which $1 million pertained to each of the first three quarters of fiscal 2014 and each quarter of fiscal 2013. The amounts were not material individually or in the aggregate to current or prior periods.

[2] Our pharmaceutical distribution contract with Walgreens expired on August 31, 2013. Our pharmaceutical distribution contract with Express Scripts, Inc. expired on September 30, 2012.

[3] Corporate revenue consists of the elimination of inter-segment revenue and other revenue not allocated to the segments.