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Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	Sep. 30, 2014	Dec. 31, 2019	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, description		Options and RSUs granted to our non-employee directors vest in full upon completion of one year of service on the Board following the date of the grant
Total unrecognized share-based compensation cost related to stock options		$ 0.0
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period of share-based compensation vested, years		4 years
Stock options [Member] | Share-based compensation granted after December 5, 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expire from date of grant, years		8 years
Stock options [Member] | Share-based compensation granted prior to December 5, 2012 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expire from date of grant, years		10 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period of share-based compensation vested, years	4 years
Total unrecognized share-based compensation cost related to RSUs		$ 59.0
Total unrecognized share-based compensation cost, weighted-average period, years		2 years 6 months
Restricted Stock Units (RSUs) [Member] | Non Employee Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period of share-based compensation vested, years		1 year
The 2017 Plan [Member] | Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant		300,000
The 2010 Plan [Member] | Options and Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant		5,200,000
2012 Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares approved			2,000,000.0
Shares issued under the Plan		500,000

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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