Stockholders' Equity - Share Repurchases in the Open Market (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |
12 Months Ended | ||
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Sep. 30, 2021 |
Sep. 30, 2020 |
Sep. 30, 2019 |
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| Class of Stock [Line Items] | |||
| Total cost | $ 8,676 | $ 8,114 | $ 8,607 |
| Class A common stock | |||
| Class of Stock [Line Items] | |||
| Shares repurchased in the open market (in shares) | 40 | 44 | 56 |
| Average repurchase price per share (in dollars per share) | $ 219.03 | $ 183.00 | $ 154.01 |
| Total cost | $ 8,676 | $ 8,114 | $ 8,607 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Number of shares that have been repurchased and retired during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition 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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- Definition Stock Repurchased and Retired During Period, Average Cost Per Share No definition available.
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- Details
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