Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
REVENUE:
Net revenue	$ 2,061.4	$ 1,895.7	$ 6,192.1	$ 5,617.9
Billable expenses	376.7	401.8	1,127.4	1,240.5
Total revenue	2,438.1	2,297.5	7,319.5	6,858.4
OPERATING EXPENSES:
Salaries and related expenses	1,334.4	1,251.4	4,136.7	3,874.6
Office and other direct expenses	367.9	317.0	1,144.4	974.1
Billable expenses	376.7	401.8	1,127.4	1,240.5
Cost of services	2,079.0	1,970.2	6,408.5	6,089.2
Selling, general and administrative expenses	9.8	21.6	69.3	85.5
Depreciation and amortization	69.0	44.0	213.1	134.0
Restructuring charges	0.0	0.0	33.9	0.0
Total operating expenses	2,157.8	2,035.8	6,724.8	6,308.7
OPERATING INCOME	280.3	261.7	594.7	549.7
EXPENSES AND OTHER INCOME:
Interest expense	(49.7)	(27.6)	(151.1)	(73.6)
Interest income	9.5	5.3	25.0	14.0
Other expense, net	(7.4)	(15.3)	(18.1)	(56.0)
Total (expenses) and other income	(47.6)	(37.6)	(144.2)	(115.6)
Income before income taxes	232.7	224.1	450.5	434.1
Provision for income taxes	64.6	60.7	118.7	137.0
Income of consolidated companies	168.1	163.4	331.8	297.1
Equity in net income (loss) of unconsolidated affiliates	0.3	0.1	(0.1)	(1.9)
NET INCOME	168.4	163.5	331.7	295.2
Net income attributable to noncontrolling interests	(2.8)	(2.5)	(4.6)	(2.5)
NET INCOME AVAILABLE TO IPG COMMON STOCKHOLDERS	$ 165.6	$ 161.0	$ 327.1	$ 292.7
Earnings per share, Basic	$ 0.43	$ 0.42	$ 0.85	$ 0.76
Earnings per share, Diluted	$ 0.42	$ 0.41	$ 0.84	$ 0.75
Weighted-average number of common shares outstanding, Basic	386.7	382.6	385.8	383.2
Weighted-average number of common shares outstanding, Diluted	391.8	388.4	390.3	388.4