Earnings Per Share - Convertible Senior Notes and Warrants (Details) - $ / shares shares in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Debt Instrument [Line Items]
Stock-based awards excluded from diluted EPS calculation (antidilutive) (in shares)	0.1	0.3
Treasury stock, shares, acquired	3.7
Class of warrant or right, exercise price of warrants or rights	$ 180.00
Convertible Debt Securities
Debt Instrument [Line Items]
Common stock, conversion price (in dollars per share)	$ 126.00
Stock-based awards excluded from diluted EPS calculation (antidilutive) (in shares)	3.7

Common Stock, Conversion Price

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

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Exercise price per share or per unit of warrants or rights outstanding.

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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.

+ References

No definition available.

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Number of shares that have been repurchased during the period and are being held in treasury.

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