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Financial Instruments and Fair Value - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 | Sep. 30, 2024 | Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Aggregate cost basis for non-qualified deferred compensation plan |  | $ 43,200,000 | $ 37,200,000
Acquisition earnout accruals, non-current |  | 41,832,000 | 38,601,000
Impairment |  | 16,224,000 |
Equity investment without readily determinable fair value, amount |  | 11,000,000 | 0
On-Demand Talent Reporting Unit |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Impairment | $ 14,800,000 | 14,800,000 |
Europe Reporting Unit |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Impairment | $ 1,500,000 | 1,500,000 |
Earnout | Fair Value, Inputs, Level 3 | Non-Current and Other Non-Current Liabilities |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Acquisition earnout accruals, non-current |  | 41,800,000 | 38,600,000
Contingent Compensation | Fair Value, Inputs, Level 3 | Current Accrued Salaries and Benefits |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Acquisition earnout accruals, current |  | 4,300,000 | 6,000,000
Contingent Compensation | Fair Value, Inputs, Level 3 | Non-Current Accrued Salaries and Benefits |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Acquisition earnout accruals, non-current |  | $ 17,800,000 | $ 12,900,000

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