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ACQUISITIONS (Narrative) (Details) £ / shares in Units, € in Millions, £ in Millions, $ in Millions						1 Months Ended			3 Months Ended	7 Months Ended	12 Months Ended
	Dec. 12, 2023 USD ($)	Dec. 12, 2023 GBP (£)	Oct. 01, 2021 USD ($)	Oct. 01, 2021 EUR (€)	May 24, 2021 USD ($)	Dec. 31, 2023 USD ($)	Apr. 30, 2022 USD ($)	Apr. 30, 2022 EUR (€)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2023 GBP (£)	Dec. 12, 2023 £ / shares	May 31, 2021 USD ($)
Business Acquisition [Line Items]
Cash paid for acquisitions, net											$ 99.6	$ 6.3	$ 193.0
OnTheMarket
Business Acquisition [Line Items]
Goodwill, expected tax deductible amount						$ 0.0					0.0
Transaction costs						11.0					11.0
Intangible assets	$ 55.2
Fair value of identifiable net assets acquired	120.4
OnTheMarket | North America
Business Acquisition [Line Items]
Goodwill acquired						62.8
Business Immo
Business Acquisition [Line Items]
Goodwill acquired							$ 7.1
Cash paid for acquisitions, net							6.3	€ 5.8
Intangible assets							$ 3.9
BureauxLocaux
Business Acquisition [Line Items]
Aggregate purchase price			$ 40.6	€ 35.0
Goodwill acquired									$ 27.4
Intangible assets									$ 18.3	$ 18.3			$ 18.3
Homes.com
Business Acquisition [Line Items]
Goodwill, expected tax deductible amount					$ 20.0
Intangible assets					53.4
Purchase price before adjustments																$ 150.0
Fair value of identifiable net assets acquired					152.2											$ 152.2
Business combinations cash escrow payment employee compensation post combination											5.0
Business combination tax liabilities accrual amount						6.6					6.6
Increase in revenue										13.6
Decrease in net income										$ 23.5
Homes.com | North America
Business Acquisition [Line Items]
Goodwill acquired					$ 91.9
OnTheMarket plc
Business Acquisition [Line Items]
Share price of acquisition (in pound per share) | £ / shares															£ 1.10
Payment for acquisition	117.9	£ 94.0
Liabilities incurred	2.6	2.0
Aggregate purchase price	$ 120.4	£ 96.0
Consideration payable						$ 5.1					$ 5.1			£ 4.0

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