Stock-Based Compensation (Stock-Options, Rollforward) (Details)	12 Months Ended
Dec. 31, 2020 $ / shares shares
Stock Options
Outstanding (shares), beginning balance \| shares	16,291,709
Granted (shares) \| shares	0
Exercised (shares) \| shares	(378,648)
Forfeited or expired (shares) \| shares	(1,772,337)
Outstanding (shares), ending balance \| shares	14,140,724
Exercisable (shares) \| shares	12,269,735
Weighted Average Exercise Price
Outstanding, beginning balance (USD per share) \| $ / shares	$ 58.98
Granted (USD per share) \| $ / shares	0
Exercised (USD per share) \| $ / shares	29.31
Forfeited or expired (USD per share) \| $ / shares	51.47
Outstanding, ending balance (USD per share) \| $ / shares	60.72
Exercisable (USD per share) \| $ / shares	$ 61.63

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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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No definition available.

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

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No definition available.

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

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