Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Income Statement [Abstract]
REVENUE	$ 3,443.3	$ 3,410.3
Salary and service costs	2,542.9	2,491.8
Occupancy and other costs	291.6	300.2
Real estate repositioning costs	119.2	0.0
Charges arising from the effects of the war in Ukraine	0.0	113.4
Cost of services	2,953.7	2,905.4
Selling, general and administrative expenses	89.2	96.7
Depreciation and amortization	53.9	55.2
Total Operating Expenses	3,096.8	3,057.3
OPERATING INCOME	346.5	353.0
Interest Expense	54.9	51.0
Interest Income	35.6	8.2
INCOME BEFORE INCOME TAXES AND INCOME (LOSS) FROM EQUITY METHOD INVESTMENTS	327.2	310.2
Income Tax Expense	83.4	115.5
Income (Loss) From Equity Method Investments	0.1	(0.1)
NET INCOME	243.9	194.6
Net Income Attributed To Noncontrolling Interests	16.4	20.8
NET INCOME - OMNICOM GROUP INC.	$ 227.5	$ 173.8
Net Income Per Share - Omnicom Group Inc.:
Basic	$ 1.13	$ 0.83
Diluted	$ 1.11	$ 0.83
Weighted Average Shares:
Basic	202.2	208.3
Diluted	204.5	209.8