Capital stock	12 Months Ended
Aug. 31, 2018
Capital Stock [Abstract]
Capital stock	Capital stock In connection with the Company’s capital policy, the Board of Directors has authorized share repurchase programs. In April 2017, Walgreens Boots Alliance authorized a stock repurchase program (the “April 2017 stock repurchase program”), which authorized the repurchase of up to $1.0 billion of Walgreens Boots Alliance common stock prior to the program’s expiration on December 31, 2017. In May 2017, the Company completed the April 2017 stock repurchase program, purchasing 11.8 million shares. In June 2017, Walgreens Boots Alliance authorized a new stock repurchase program, which authorized the repurchase of up to $5.0 billion of Walgreens Boots Alliance common stock prior to the program’s expiration on August 31, 2018, which authorization was increased by an additional $1.0 billion in October 2017 (as expanded, the “June 2017 stock repurchase program”). The June 2017 stock repurchase program was completed in October 2017. In June 2018, Walgreens Boots Alliance authorized a new stock repurchase program, which authorized the repurchase of up to $10.0 billion of Walgreens Boots Alliance common stock, which program has no specified expiration date. The Company purchased 72 million and 59 million shares under stock repurchase programs in fiscal 2018 and 2017 at a cost of $4.9 billion and $4.8 billion, respectively. The Company determines the timing and amount of repurchases based on its assessment of various factors including prevailing market conditions, alternate uses of capital, liquidity, the economic environment and other factors. The timing and amount of these purchases may change at any time and from time to time. The Company has repurchased, and may from time to time in the future repurchase, shares on the open market through Rule 10b5-1 plans, which enable a company to repurchase shares at times when it otherwise might be precluded from doing so under insider trading laws. In addition, the Company continued to repurchase shares to support the needs of the employee stock plans. Shares totaling $289 million were purchased to support the needs of the employee stock plans during fiscal 2018 as compared to $457 million and $1 billion in fiscal 2017 and fiscal 2016, respectively. At August 31, 2018, 33 million shares of common stock were reserved for future issuances under the Company’s various employee benefit plans.

Capital stock

In connection with the Company’s capital policy, the Board of Directors has authorized share repurchase programs. In April 2017, Walgreens Boots Alliance authorized a stock repurchase program (the “April 2017 stock repurchase program”), which authorized the repurchase of up to $1.0 billion of Walgreens Boots Alliance common stock prior to the program’s expiration on December 31, 2017. In May 2017, the Company completed the April 2017 stock repurchase program, purchasing 11.8 million shares. In June 2017, Walgreens Boots Alliance authorized a new stock repurchase program, which authorized the repurchase of up to $5.0 billion of Walgreens Boots Alliance common stock prior to the program’s expiration on August 31, 2018, which authorization was increased by an additional $1.0 billion in October 2017 (as expanded, the “June 2017 stock repurchase program”). The June 2017 stock repurchase program was completed in October 2017. In June 2018, Walgreens Boots Alliance authorized a new stock repurchase program, which authorized the repurchase of up to $10.0 billion of Walgreens Boots Alliance common stock, which program has no specified expiration date. The Company purchased 72 million and 59 million shares under stock repurchase programs in fiscal 2018 and 2017 at a cost of $4.9 billion and $4.8 billion, respectively.

The Company determines the timing and amount of repurchases based on its assessment of various factors including prevailing market conditions, alternate uses of capital, liquidity, the economic environment and other factors. The timing and amount of these purchases may change at any time and from time to time. The Company has repurchased, and may from time to time in the future repurchase, shares on the open market through Rule 10b5-1 plans, which enable a company to repurchase shares at times when it otherwise might be precluded from doing so under insider trading laws.

In addition, the Company continued to repurchase shares to support the needs of the employee stock plans. Shares totaling $289 million were purchased to support the needs of the employee stock plans during fiscal 2018 as compared to $457 million and $1 billion in fiscal 2017 and fiscal 2016, respectively. At August 31, 2018, 33 million shares of common stock were reserved for future issuances under the Company’s various employee benefit plans.