Employee Stock Purchase Program Discount Rate From Fair Market Value

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Non Employee Directors Fair Value Of Stock Awards

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Non Employee Directors' Stock Awards Percentage Vested on Date of the Next Annual Stockholders' Meeting following Grant Date

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Contractual Term

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Share-based Compensation Arrangement by Share-based Payment Award, Deferred Stock Obligation, Number of Shares

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Share-based Compensation Arrangement by Share-based Payment Award, Deferred Stock Obligation, Shares Delivery Period

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Share-based Compensation Arrangement by Share-based Payment Award, Number of Equal Annual Vesting Installments

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of noncash expense for share-based payment arrangement.

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

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Stock Based Compensation - Stock Compensation Plans (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($) installment shares	Mar. 31, 2021 USD ($) shares	Dec. 31, 2021 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation \| $	$ 11,764	$ 10,372
Unrecognized compensation costs \| $	$ 108,400
Unrecognized compensation costs, period for recognition	2 years 7 months 17 days
Number of equal annual vesting installments \| installment	3
Options outstanding, number of underlying shares (in shares)	1,578,000		1,578,000
Marketing Partner
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs \| $	$ 7,700
Unrecognized compensation costs, period for recognition	2 years 6 months 3 days
Additional share based compensation \| $	$ 800	$ 900
Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term	10 years
Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, number of underlying shares (in shares)	700,000
2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of stock awards \| $	$ 150
Vesting percentage	100.00%
2005 Plan \| Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	8,300,000
2005 Plan \| Common Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	25,700,000
Director Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of stock awards \| $	$ 100
Obligation to issue share (in shares)	1
Period shares delivered following termination of director's service	6 months
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
ESPP discount rate from fair market value	15.00%
ESPP shares granted during period (in shares)	69,800	59,000
ESPP \| Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	2,700,000
ESPP \| Common Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	1,700,000
Minimum \| 2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (over)	2 years
Maximum \| 2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (over)	5 years