Stock-Based Compensation - Stock Option Awards (Details) - Stock Options and SARs $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) $ / shares shares
Shares
Balance at beginning of period (shares) \| shares	7,742
Granted (shares) \| shares	795
Exercised or settled (shares) \| shares	(1,530)
Forfeited (shares) \| shares	(255)
Expired (shares) \| shares	(6)
Balance at end of period (shares) \| shares	6,746
Vested (shares) \| shares	4,351
Weighted-Average Exercise Price (per share)
Balance at beginning of period (USD per share) \| $ / shares	$ 18.47
Granted (USD per share) \| $ / shares	45.78
Exercised or settled (USD per share) \| $ / shares	16.11
Forfeited (USD per share) \| $ / shares	30.77
Expired (USD per share) \| $ / shares	13.01
Balance at end of period (USD per share) \| $ / shares	21.76
Vested (USD per share) \| $ / shares	$ 15.89
Weighted average remaining contractual term of options outstanding	5 years 8 months 12 days
Weighted average remaining contractual term of options vested	4 years 4 months 24 days
Aggregate intrinsic value of in-the-money options outstanding \| $	$ 268.7
Aggregate intrinsic value of in-the-money options vested \| $	$ 198.2

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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