Guarantees (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]
Parent company guarantees on lease obligations	$ 580.4	$ 588.1
Parent company guarantees relating to credit facilities	329.2	279.6
Assets pledged as security for parent company guarantees	$ 0

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