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

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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Purchase price of common stock expressed as a percentage of its fair value.

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Stock-Based Compensation - Additional Information (Detail) $ in Millions	1 Months Ended					9 Months Ended
	Jun. 30, 2023 shares	Jun. 30, 2022 shares	Jun. 30, 2021 shares	Jun. 30, 2020 shares	Jun. 30, 2019 shares	Sep. 30, 2023 USD ($) Period shares	Dec. 31, 2022 shares	Sep. 30, 2022 shares
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, option to be granted at percentage of fair value of common stock						85.00%
Employee Stock Purchase Plan, offering period						12 months
Number of purchase periods within each offering period \| Period						2
Increase in shares of common stock authorized for issuance				1,500,000
Aggregate number of shares of common stock reserved for future issuance						800,000
2008 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, option to be granted at percentage of fair value of common stock						100.00%
Increase in shares of common stock authorized for issuance	7,000,000	12,000,000	7,600,000	5,000,000	11,800,000
Aggregate number of shares of common stock reserved for future issuance						40,000,000
Stock-based compensation, award term						10 years
Performance-based stock options, outstanding						2,600,000
Outstanding options and other stock based awards						14,528,000	15,756,000	14,500,000
Number of shares available for future issuance						14,000,000
2008 Equity Incentive Plan \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period						4 years
2008 Equity Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of unvested Restricted Stock Units						11,533,000	8,497,000
2008 Equity Incentive Plan \| Performance-based Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Stock Purchase Plan, authorized shares for issuance						500,000
2008 Equity Incentive Plan \| Performance-based Cash Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option plan granted on cash award \| $						$ 1.0
2008 Equity Incentive Plan \| Minimum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period						3 years
2008 Equity Incentive Plan \| Maximum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period						4 years