Stock-Based Awards - Additional Information (Details) - $ / shares shares in Thousands	1 Months Ended	9 Months Ended
May 16, 2018	Sep. 30, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price of stock option	$ 17.33
Number of stock options granted in exchange for options eligible for exchange	700	2,312
Stock Option Exchange Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option exchange program commencement date	Apr. 18, 2018
Option exchange program expiration date	May 16, 2018
Eligible stock options tendered by employees	1,000
Percentage of eligible stock options tendered by employees	73.00%
Stock Option Exchange Program \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price of stock option	$ 21.72

Percentage of eligible stock options tendered by employee for stock option exchange program

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- Definition

Share based compensation arrangement, eligible stock options tendered by employees

+ References

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- Definition

Share based compensation arrangement, stock option exchange program expiration date.

+ References

No definition available.

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- Definition

Share based compensation arrangement, stock option exchange program, start date.

+ References

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- Definition

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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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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