Consolidated Balance Sheets (Parenthetical) - $ / shares shares in Millions	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Common stock and additional paid-in capital, par value (in usd per share)	$ 0.0001	$ 0.0001
Common stock and additional paid-in capital, shares authorized	2,750.0	2,750.0
Common stock and additional paid-in capital, shares outstanding	591.4	629.6

Face amount or stated value per share of common stock.

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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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
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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