Stockholders' Equity (Deficit) - Summary of Number of Shares Authorized to be Issued and Available for Grant (Details) - shares	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
2017 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares authorized to be issued	3,944,750,000	2,945,443,000	997,785,000
Shares available for grant	23,153,000	848,241,000	137,908,000
2013 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares authorized to be issued	2,047,269,000	2,047,269,000	2,058,619,000
Shares available for grant			1,550,000

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.

No definition available.

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- Definition

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

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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

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-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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