Stock-Based Compensation - Stock Option Activity (Detail)	12 Months Ended
Dec. 31, 2019 $ / shares shares
Options
Outstanding at December 31, 2018 \| shares	4,023,822
Granted \| shares	652,559
Exercised \| shares	(760,807)
Expired/forfeited \| shares	(90,358)
Outstanding at December 31, 2019 \| shares	3,825,216
Weighted-Average Exercise Price
Outstanding at December 31, 2018 \| $ / shares	$ 40.83
Granted \| $ / shares	47.85
Exercised \| $ / shares	22.71
Expired/forfeited \| $ / shares	56.35
Outstanding at December 31, 2019 \| $ / shares	$ 45.27

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

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