CONSOLIDATED CONDENSED STATEMENTS OF EARNINGS (UNAUDITED) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017
Income Statement [Abstract]
Sales	$ 33,021	$ 29,446	$ 63,761	$ 57,947
Cost of sales	24,925	21,885	48,324	43,270
Gross profit	8,096	7,561	15,437	14,677
Selling, general and administrative expenses	6,318	6,124	12,225	11,810
Equity earnings in AmerisourceBergen	202	42	90	59
Operating income	1,980	1,479	3,302	2,926
Other income (expense)	9	(15)	(128)	(14)
Earnings before interest and income tax provision	1,989	1,464	3,174	2,912
Interest expense, net	151	172	300	345
Earnings before income tax provision	1,838	1,292	2,874	2,567
Income tax provision	503	246	730	466
Post tax earnings from other equity method investments	14	16	27	28
Net earnings	1,349	1,062	2,171	2,129
Net earnings attributable to noncontrolling interests	0	2	1	15
Net earnings attributable to Walgreens Boots Alliance, Inc.	$ 1,349	$ 1,060	$ 2,170	$ 2,114
Net earnings per common share:
Basic (in dollars per share)	$ 1.36	$ 0.98	$ 2.17	$ 1.96
Diluted (in dollars per share)	1.36	0.98	2.16	1.94
Dividends declared per share (in dollars per share)	$ 0.400	$ 0.375	$ 0.800	$ 0.750
Weighted average common shares outstanding:
Basic (in shares)	991.0	1,079.7	998.6	1,080.9
Diluted (in shares)	995.5	1,085.5	1,003.3	1,086.9