Note 1 - Description of the Business	12 Months Ended
Dec. 31, 2023
Notes to Financial Statements
Business Description and Basis of Presentation [Text Block]	1. Description of the business Colliers International Group Inc. (“Colliers” or the “Company”) provides commercial real estate professional services and investment management to corporate and institutional clients in 34 countries around the world (66 countries including affiliates and franchisees). Colliers’ primary service lines are Outsourcing & Advisory, Investment Management (“IM”), Leasing and Capital Markets. Operationally, Colliers is organized into four distinct segments: Americas; Europe, Middle East and Africa (“EMEA”); Asia and Australasia (“Asia Pacific”) and Investment Management.

The entire disclosure for the business description and basis of presentation concepts. Business description describes the nature and type of organization including but not limited to organizational structure as may be applicable to holding companies, parent and subsidiary relationships, business divisions, business units, business segments, affiliates and information about significant ownership of the reporting entity. Basis of presentation describes the underlying basis used to prepare the financial statements (for example, US Generally Accepted Accounting Principles, Other Comprehensive Basis of Accounting, IFRS).

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