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Share-based Compensation Arrangement By Share-based Payment Award, Award Vesting Trigger Stock Price

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Share-based Compensation Arrangement By Share-based Payment Award, Fair Value Assumptions, Cost Of Equity Rate

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

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Amount of cost for defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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Amount of cost capitalized for award under share-based payment arrangement.

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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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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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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Rate of weighted-average expected volatility for award under share-based payment arrangement.

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

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

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COMPENSATION ARRANGEMENTS - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Apr. 30, 2019	Apr. 30, 2010	Jan. 31, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future issuance (in shares)	2,055,180
Total stock-based compensation expense	$ 33,169	$ 40,745	$ 81,615
Share-based payment arrangement, amount capitalized	$ 3,700	4,500	7,100
Number of shares available for grant (in shares)	100,500,000
United States
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Defined contribution plan, employer matching contribution, percent of match	50.00%
Defined contribution plan, employer matching contribution, percent of employees' eligible compensation	6.00%
Defined contribution plan, vesting period	3 years
Defined contribution plan, cost	$ 6,700	$ 6,600	$ 9,400
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	1,000,000
Shares issued under employee stock purchase plan (in shares)	49,399	69,371	74,300
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period, weighted average grant date fair value (in usd per shares)	$ 31.48	$ 24.92	$ 68.80
Fair value of restricted stock award vested	$ 48,800	$ 19,200	$ 43,800
Unrecognized compensation costs, amount	$ 49,900
Unrecognized compensation costs, period for recognition	1 year 1 month 9 days
Restricted stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Restricted stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Market-based Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period, weighted average grant date fair value (in usd per shares)	$ 0
Award vesting trigger stock price (in USD per share)	$ 120.00
Award vesting term, umber of consecutive trading days	30 days
Share-based compensation arrangement by share-based payment award, fair value assumptions, weighted average volatility rate	49.80%
Share-based compensation arrangement by share-based payment award, fair value assumptions, cost of equity rate	12.80%
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted in period, weighted average grant date fair value (in usd per shares)	$ 15.44
Unrecognized compensation costs, amount	$ 100
Unrecognized compensation costs, period for recognition	11 months 26 days
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 585	662	1,482
Marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	748	1,522	5,809
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	31,836	36,826	74,324
Restructuring and related charges
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 0	$ 1,735	$ 0
2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for awards (in shares)						3,230,925
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for awards (in shares)					1,000,000
2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for awards (in shares)				9,375,000