Aggregate number of common shares reserved for future issuance.

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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.

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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.

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No definition available.

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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- Definition

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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Stock-Based Compensation and Employee Benefit Plans - Equity Incentive Plan (Additional Information) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average exercise price, outstanding options (in dollars per share)	$ 20.76	$ 25.93	$ 26.42
2012 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Weighted average exercise price, outstanding options (in dollars per share)	$ 27.12
2012 Equity Incentive Plan \| Class B common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of outstanding options (in shares)	9,982,756
Stock-based compensation vesting period	4 years
2018 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years
Weighted average exercise price, outstanding options (in dollars per share)	$ 9.42
2018 Equity Incentive Plan \| Class A common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of outstanding options (in shares)	5,998,406
Shares reserved for future issuance (in shares)		20,278,268
Number of common stock reserved for issuance (in shares)		26,666,667
Stock option \| 2018 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)	17,233,144
RSUs \| 2012 Equity Incentive Plan \| Class B common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (in shares)	6,656,094
RSUs \| 2018 Equity Incentive Plan \| Class A common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of outstanding options (in shares)	3,456,172