Consolidated Statements of Comprehensive Income - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
NET INCOME		$ 18.1	$ 2.7
Foreign currency translation:
Foreign currency translation adjustments		50.6	56.9
Reclassification adjustments recognized in net income	[1]	1.2	(1.0)
Foreign currency transaction and translation adjustment, net of tax		51.8	55.9
Available-for-sale securities:
Changes in fair value of available-for sale securities		0.1	0.1
Net unrealized gains/losses on available-for-sale securities, net of tax		0.1	0.1
Derivative instruments:
Recognition of previously unrealized losses in net income		0.5	0.5
Income tax effect		(0.2)	(0.2)
Net unrecognized gains/losses on derivative instruments, net of tax		0.3	0.3
Defined benefit pension and other postretirement plans:
Net actuarial gains for the period		0.0	0.2
Amortization of unrecognized losses, transition obligation and prior service cost included in net income		1.7	2.7
Other		(0.2)	0.1
Income tax effect		(0.1)	(0.7)
Defined benefit pension and other postretirement plans adjustment, net of tax		1.4	2.3
Other comprehensive income, net of tax		53.6	58.6
TOTAL COMPREHENSIVE INCOME		71.7	61.3
Less: comprehensive loss attributable to noncontrolling interests		(2.9)	(2.2)
COMPREHENSIVE INCOME ATTRIBUTABLE TO IPG		$ 74.6	$ 63.5

[1] These foreign currency translation adjustments are primarily a result of the sales of businesses