Number Of Countries With Primary Office Locations

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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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Cost of product sold and service rendered, excluding depreciation, depletion, and amortization.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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BASIS OF FINANCIAL STATEMENT PREPARATION (Details) $ in Millions	3 Months Ended				6 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2024 USD ($) segment country	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Concentration Risk [Line Items]
Number of reportable segments \| segment	1
Number of operating segments \| segment	1
Number of countries with primary office locations \| country	5
Selling, general and administrative expenses, exclusive of depreciation and amortization	$ 120.1	$ 106.8	$ 97.8	$ 116.8	$ 214.6	$ 321.4	$ 448.1	$ 416.1
Decrease of direct costs	$ (554.2)	$ (563.8)	$ (568.7)	(541.5)	$ (1,110.2)	$ (1,674.0)	$ (2,251.9)	$ (2,112.6)
Interest income (expense)				0.1
Reclassifications
Concentration Risk [Line Items]
Selling, general and administrative expenses, exclusive of depreciation and amortization				45.3
Decrease of direct costs				$ 45.3
Customer one \| Accounts receivable and unbilled services \| Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage	19.30%
Customer one \| Revenue \| Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage	14.00%			10.00%
Customer two \| Accounts receivable and unbilled services \| Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage	11.00%
Customer two \| Revenue \| Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage	13.00%
Pharmaceutical company one \| Accounts receivable and unbilled services \| Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage							17.00%
Pharmaceutical company two \| Accounts receivable and unbilled services \| Customer concentration risk
Concentration Risk [Line Items]
Concentration risk, percentage							11.20%