Equity and Noncontrolling Interests Equity and Noncontrolling Interests - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Equity, Class of Treasury Stock [Line Items]
Repurchases and retirements of ordinary shares	$ 340		$ 1,001	$ 1,467
Stock Repurchase Program, Increase in Authorized Amount		$ 4,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 5,400		$ 5,400		$ 2,000

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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