Employee Incentive Plans - Schedule of Stock Reserved for Future Issuance (Detail) - shares	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total reserved for future issuance (shares)	33,363,329	31,318,320
Available for future RSU, PBRSU and stock option grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Available for grant (in shares)	15,172,055	12,552,761
Unvested RSUs, PBRSUs and stock options outstanding (in shares)	13,029,414	14,631,526
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Available for grant (in shares)	5,161,860	4,134,033

Share-Based Compensation Arrangement By Share-based Payment Award, Equity Instruments, Nonvested, Number

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

+ References

No definition available.

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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

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