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Performance Shares, Advertiser Billing Period

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Performance Shares, EBITDA Target Period

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Performance Shares, Stock Closing Price Period

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Performance Shares, Vesting Condition Period

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Share-based Compensation Arrangement By Share-based Payment Award, Award Vesting Rights, Achievement Percentage

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Share-Based Compensation Arrangement By Share-Based Payment Award, Non-Option Equity Instruments, Performance Conditions

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Share-based Compensation Arrangement by Share-based Payment Award, Number Of Shares Authorized, Annual Percentage Increase

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Share-Based Payment Arrangement, Number Of Vesting Tranches

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Amount of increase in lease obligation from new lease.

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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 cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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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 number of grants made 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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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 additional shares authorized for issuance under share-based payment arrangement.

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

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Percentage of vesting of award under share-based payment arrangement.

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

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STOCK-BASED COMPENSATION - Narrative (Details) $ in Millions			1 Months Ended						3 Months Ended
	Jan. 01, 2021 shares	Feb. 08, 2018	May 02, 2023 USD ($) shares	Mar. 31, 2022	Jul. 31, 2021 shares	Apr. 30, 2021 tranche shares	Apr. 30, 2020 user shares	Apr. 30, 2019 tranche shares	Mar. 31, 2023 USD ($) shares	Mar. 31, 2022 USD ($)	Dec. 31, 2022 shares	Dec. 31, 2021	Sep. 30, 2021 shares	Jan. 01, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)											405,830
Number of shares authorized, annual increase									5.00%
Number of additional shares authorized (in shares)	1,673,858
Lease obligation incurred \| $									$ 0.4	$ 0.2
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost not yet recognized									2 years 9 months
Granted (in shares)									533,000
Unvested PSU (in shares)									5,974,000		5,956,000
Restricted stock units \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)									533,308
Restricted stock units \| Share-based Compensation Award, Tranche One \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period									4 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested PSU (in shares)								1,252,500
Number of vesting tranches \| tranche								4
Minimum growth rate period								12 months
Advertiser billing period								12 months
EBITDA target period								12 months
Stock closing price period								30 days
Performance Shares \| 2020 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested PSU (in shares)							476,608				269,202		6,666
ARPU vesting condition period							4 years
Performance Shares \| 2021 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested PSU (in shares)						110,236							6,667
Number of vesting tranches \| tranche						2
ARPU vesting condition period						4 years
Performance Shares \| Bridg PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested PSU (in shares)					34,344
Performance Shares \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage				25.00%
Performance Shares \| Share-based Compensation Award, Tranche One \| 2020 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						12 months	12 months
Unvested PSU (in shares)							443,276
Performance conditions \| user							0.50
Performance Shares \| Share-based Compensation Award, Tranche One \| 2021 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						12 months
Unvested PSU (in shares)						55,118
Performance Shares \| Share-based Compensation Award, Tranche One \| Bridg PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage					50.00%
Performance Shares \| Share-based Compensation Award, Tranche One \| Minimum \| Bridg PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Achievement percentage					80.00%
Performance Shares \| Share-based Compensation Award, Tranche One \| Maximum \| Bridg PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Achievement percentage					99.999%
Performance Shares \| Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage				50.00%
Performance Shares \| Share-based Compensation Award, Tranche Two \| 2020 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period							6 months
Unvested PSU (in shares)							33,332
Performance conditions \| user							0.25
Performance Shares \| Share-based Compensation Award, Tranche Two \| 2021 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period						6 months
Unvested PSU (in shares)						55,118
Performance Shares \| Share-based Compensation Award, Tranche Two \| Bridg PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage					100.00%
Achievement percentage					100.00%
Performance Shares \| Share-based Payment Arrangement, Tranche Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage				50.00%
Performance Shares \| Share-based Payment Arrangement, Tranche Three \| 2020 PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period							12 months
Performance conditions \| user							0.25
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized, annual increase												1.00%
ESPP, purchase price percentage		85.00%
ESPP, number of shares authorized, annual increase (in shares)									500,000		878,969,000			334,771,000
Subsequent Event \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			1,995,000
Compensation not yet recognized, awards other than options \| $			$ 9.8