DISCONTINUED OPERATIONS - Earnings from Discontinued Operations (Details) - Discontinued operations, held-for-sale - Enabling Services segment disposal - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues	$ 65.7	$ 69.8
Costs and expenses:
Direct costs, exclusive of depreciation and amortization	41.4	46.1
Selling, general and administrative expenses, exclusive of depreciation and amortization	15.6	15.0
Depreciation and amortization	1.6	2.2
Long-lived and goodwill asset impairments	24.0	0.0
Restructuring and other charges	0.5	0.6
Total costs and expenses	83.1	63.9
Operating income (loss)	(17.4)	5.9
Other expense:
Foreign exchange gain (loss)	0.0	(0.3)
Income (loss) from discontinued operations before income taxes	(17.4)	5.6
Provision for income taxes	3.8	1.1
Income (loss) from discontinued operations, net of tax	$ (21.2)	$ 4.5

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Amount before tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal.

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Amount of tax expense (benefit) attributable to income (loss) from operations classified as a discontinued operation. Excludes tax expense (benefit) for gain (loss) on disposal and for provision for gain (loss) until disposal.

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