Commitments and Contingencies (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Lease guarantees	$ 827.8	$ 857.3
Credit facility guarantees	$ 413.8	$ 395.6

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the credit facilities guarantees or each group of similar guarantees.

No definition available.

Name:	ipg_GuaranteeObligationsCurrentCarryingValueCreditfacilities
Namespace Prefix:	ipg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant