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Share Capital (Details Textual) $ / shares in Units, $ in Thousands |  |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2022 USD ($) shares | Nov. 08, 2021 shares | Oct. 07, 2021 shares | Aug. 02, 2021 $ / shares shares | Dec. 31, 2022 USD ($) vote $ / shares shares | Dec. 31, 2021 USD ($) $ / shares shares | Dec. 31, 2020 USD ($) | Mar. 01, 2023 USD ($) | Mar. 23, 2022 USD ($)
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  |  |  |  | $ 125,000
Shares exchanged that trigger employee tax withholding obligation | shares |  |  |  |  | 5,000,000 |  |  |  |
Employee tax withholding obligation | shares |  |  |  |  | 2,000,000 |  |  |  |
Equity Exchange, Tax Withholding Obligation |  |  |  |  | $ 14,900 |  |  |  |
Stock Repurchased and Retired During Period, Shares | shares | 7,194,000 |  |  |  |  |  |  |  |
Stock Repurchase Program, Remaining Authorized Repurchase Amount |  |  |  |  | $ 73,309 |  |  |  |
Stock Repurchased and Retired During Period | $ / shares |  |  |  |  | $ 7.17 |  |  |  |
Repurchase of Common Stock | $ 51,547 |  |  |  | $ 51,540 | $ 0 | $ 0 |  |
Common Stock, Capital Shares Reserved for Future Issuance | shares |  |  |  |  | 12,858,000 | 2,839,000 |  |  |
Stock-based compensation |  |  |  |  | $ 33,152 | $ 75,032 |  |  |
Increase (Decrease) in Profit Interest Award, Liability |  |  |  |  | $ (4,179) | $ 536 |  |  |
Subsequent event |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  |  |  | $ 250,000 |
Stock Repurchase Program, Increase in Authorized Amount |  |  |  |  |  |  |  | $ 125,000 |
Performance-Based Awards |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Grant date fair value of options granted (in dollars per share) | $ / shares |  |  |  |  | $ 7.74 | $ 8.68 |  |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition |  |  |  |  | 1 year 10 months 9 days | 2 years 4 months 13 days |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms |  |  |  |  | 1 year 10 months 9 days | 2 years 4 months 13 days |  |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount |  |  |  |  | $ 12,781 | $ 8,221 |  |  |
Stock Appreciation Rights (SARs) |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Grant date fair value of options granted (in dollars per share) | $ / shares |  |  |  |  | $ 2.78 | $ 2.79 |  |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition |  |  |  |  | 1 year 5 months 12 days | 1 year 1 month 24 days |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate |  |  |  |  | 4.00% | 1.00% |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate |  |  |  |  | 0.00% | 0.00% |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period |  |  |  |  |  | 5 years |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number | shares |  |  |  |  | 3,845,000 | 1,950 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding |  |  |  |  | $ 11,063 | $ 19,677 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms |  |  |  |  | 1 year 5 months 12 days | 1 year 1 month 24 days |  |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount |  |  |  |  | $ 1,175 | $ 4,639 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term |  |  |  |  | 4 years |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares | shares |  |  |  |  | 1,943 | 1,950 |  |  |
Stock Appreciation Rights (SARs) | Minimum |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Grant date fair value of options granted (in dollars per share) | $ / shares |  |  |  |  |  | $ 2.20 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term |  |  |  |  | 2 years | 2 years 9 months 18 days |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate |  |  |  |  | 37.00% | 35.50% |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  |  |  |  |  | 1 year |  |  |
Stock Appreciation Rights (SARs) | Maximum |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Grant date fair value of options granted (in dollars per share) | $ / shares |  |  |  |  |  | $ 3.66 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term |  |  |  |  | 3 years | 4 years |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate |  |  |  |  | 41.40% | 38.10% |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  |  |  |  |  | 3 years |  |  |
Time-Based Awards |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Grant date fair value of options granted (in dollars per share) | $ / shares |  |  |  |  | $ 7.07 | $ 5.49 |  |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition |  |  |  |  | 7 months 24 days | 4 months 13 days |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms |  |  |  |  | 7 months 24 days | 4 months 13 days |  |  |
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount |  |  |  |  | $ 16,449 | $ 15,376 |  |  |
Restricted Stock and Restricted Stock Units |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value |  |  |  |  | 77,332 | 1,527 |  |  |
Other Awards |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Profit interest award liability |  |  |  |  | 20,961 | 36,418 |  |  |
Stock Compensation Award |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Stock-based compensation |  |  |  |  | 36,663 |  |  |  |
Share-Based Payment Arrangement, Noncash Expense, Income Tax Benefit |  |  |  |  | $ 4,106 | $ 5,289 |  |  |
Common Class A |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Common Stock, Shares Authorized | shares |  |  |  |  | 1,000,000,000 |  |  |  |
Common Stock, Shares, Issued | shares |  |  |  |  | 131,720,000 |  |  |  |
Common stock, voting rights, number of votes per share | vote |  |  |  |  | 1 |  |  |  |
Shares issued in exchange | shares |  | 20,949,000 | 12,087,000 |  | 19,061,000 |  |  |  |
Common Class B |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Common Stock, Shares Authorized | shares |  |  |  |  | 5,000 |  |  |  |
Common Stock, Shares, Issued | shares |  |  |  |  | 4,000 |  |  |  |
Common stock, voting rights, number of votes per share | vote |  |  |  |  | 20 |  |  |  |
Common Class C |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Common Stock, Shares Authorized | shares |  |  |  |  | 250,000,000 |  |  |  |
Common Stock, Shares, Outstanding | shares |  |  |  |  | 160,909,000 |  |  |  |
MDC | Common Class B |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Common Stock, Par or Stated Value Per Share | $ / shares |  |  |  | $ 0.001 |  |  |  |  |
MDC | Common Class C | Stagwell Media |  |  |  |  |  |  |  |  |
Share Capital [Line Items] |  |  |  |  |  |  |  |  |
Shares issued in acquisition | shares |  |  |  | 179,970,000 |  |  |  |  |

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(ii) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(2) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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