Stock Based Compensation - Narrative (Details) shares in Millions	12 Months Ended
Dec. 31, 2019 shares
Additional Disclosures for equity-based plans
Shares available for grant (in shares)	3
Stock Options
Additional Disclosures for equity-based plans
Vesting period	4 years
Time-based RSUs and RSAs
Additional Disclosures for equity-based plans
Vesting period	4 years
Time-based RSUs and RSAs \| Minimum
Additional Disclosures for equity-based plans
Percent of share value	0.00%
Time-based RSUs and RSAs \| Maximum
Additional Disclosures for equity-based plans
Percent of share value	200.00%
Employee Stock
Additional Disclosures for equity-based plans
Shares available for grant (in shares)	3
Common Class A \| Stock Options \| Maximum
Additional Disclosures for equity-based plans
Contractual term	10 years
Employee Stock Purchase Plan
Additional Disclosures for equity-based plans
Stock options granted percentage of fair market value on offering date	85.00%
Stock options granted percentage of fair market value on purchase date	85.00%
Share-based Payment Arrangement, Tranche One \| Performance-based RSUs and RSAs
Additional Disclosures for equity-based plans
Vesting period	1 year
Amount of shares that are expected to vest (as a percent )	50.00%

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.

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Discount rate from fair value on offering date that participants pay for shares.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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