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Stock-Based Compensation - Additional Information (Detail) $ in Millions | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 shares | Jun. 30, 2020 shares | Jun. 30, 2019 shares | Mar. 31, 2022 USD ($) Period shares | Dec. 31, 2021 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 |  |  |  | 1,500,000 |
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 | 7,600,000 | 5,000,000.0 | 11,800,000 |  |
Aggregate number of shares of common stock reserved for future issuance |  |  |  | 27,500,000 |
Stock-based compensation, award term |  |  |  | 10 years |
Performance-based stock options, outstanding |  |  |  | 1,400,000 |
Outstanding options and other stock based awards |  |  |  | 16,022,000 | 15,092,000
Number of shares available for future issuance |  |  |  | 3.4 |
2008 Equity Incentive Plan | Stock Options |  |  |  |  |
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 |  |  |  | 8,122,000 | 6,689,000
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 |

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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