Common Stock and Stock-Based Compensation - Share-based Compensation, Options (Details) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, beginning balance	2,556,365	2,786,568
Granted	628,133	672,092
Exercised	(23,032)	(502,322)
Forfeited or expired	(65,305)	(399,973)
Outstanding, ending balance (in shares)	3,096,161	2,556,365	2,786,568
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding, beginning balance	$ 62.78	$ 57.13
Granted	44.28	59.17
Exercised	10.33	17.19
Outstanding, ending balance	$ 59.29	$ 62.78	$ 57.13
Non- Exercisable options outstanding (in shares)	1,070,054	1,074,456	1,349,339
Exercisable options outstanding (in shares)	2,026,107	1,481,909	1,437,229

Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Non-exercisable, Number

No definition available.

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- Definition

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.

+ References

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- Definition

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

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No definition available.

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- Definition

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

+ References

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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- Definition

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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- Definition

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

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- Definition

Number of fully vested and expected to vest exercisable options that may 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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- Definition

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

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- Definition

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

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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