CONSOLIDATED BALANCE SHEET (Parenthetical) (unaudited) - $ / shares shares in Millions	Dec. 31, 2018	Sep. 30, 2018
Treasury Stock (shares)	393.1	393.1
Common Class A
Common Stock, Par or Stated Value Per Share (in usd per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized	375.0	375.0
Common Stock, Shares, Outstanding	49.4	49.4
Common Class B
Common Stock, Par or Stated Value Per Share (in usd per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized	5,000.0	5,000.0
Common Stock, Shares, Outstanding	353.7	353.7

Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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-Name Accounting Standards Codification
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