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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, 2026 shares	Jun. 30, 2025 shares	Jun. 30, 2024 shares	Jun. 30, 2023 shares	Jun. 30, 2022 shares	Jun. 30, 2021 shares	Jun. 30, 2020 shares	Jun. 30, 2019 shares	Sep. 30, 2026 USD ($) Period shares	Dec. 31, 2025 shares	Dec. 31, 2024 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			2,000,000				1,500,000
Aggregate number of shares of common stock reserved for future issuance									1,300,000
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
Stock-based compensation, award term									10 years
Outstanding options and other stock based awards									8,056,000	10,027,000
Number of additional awards granted											0
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									19,256,000	17,504,000
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
2024 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	10,000,000	10,000,000
Aggregate number of shares of common stock reserved for future issuance									27,300,000
Stock-based compensation, award term									10 years
Performance-based stock options, outstanding									3,600,000
Number of shares available for future issuance									16,100,000
Number of additional shares available for grant and issurance											5,000,000
2024 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
2024 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
2024 Equity Incentive Plan \| Minimum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period									2 years
2024 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
Amended 2008 Plan and 2024 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options and other stock based awards									8,000,000
Amended 2008 Plan and 2024 Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of unvested Restricted Stock Units									19,300,000