Aggregate number of common shares reserved for future issuance.

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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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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Description of terms of share-based payment arrangement. Includes, but is not limited to, type of award or grantee and reason for issuance.

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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.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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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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Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
	Sep. 30, 2014	Mar. 31, 2020
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		$ 50.3
Total unrecognized share-based compensation cost, weighted-average period, years		2 years 3 months 18 days
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
2003 Plan [Member] \| Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant		200,000
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 available for issuance under the Plan		500,000