Supplementary Data Other Income, Net (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Other Income, net (details) [Abstract]
(Losses) gains on sales of businesses and investments	$ (0.1)	$ 0.8
Vendor discounts and credit adjustments	0ipg_VendorDiscountsAndCreditAdjustments	1.5ipg_VendorDiscountsAndCreditAdjustments
Other income (expense), net	0.4us-gaap_OtherNonoperatingExpense	(0.6)us-gaap_OtherNonoperatingExpense
Other income, net	$ 0.3us-gaap_OtherNonoperatingIncomeExpense	$ 1.7us-gaap_OtherNonoperatingIncomeExpense

Net gain (loss) on sales of businesses and investments.

No definition available.

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- Details

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- Definition

Reversal of vendor discounts and credit liabilities as a result of settlement with clients or vendors or where the statue of limitations has lapsed

+ References

No definition available.

+ Details

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- Definition

The aggregate amount of other expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating expense recognized during the period. Such amounts may include: (a) unusual costs, (b) loss on foreign exchange transactions, (c) losses on securities (net of profits), and (d) miscellaneous other expense items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.9)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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- Definition

The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

+ References

+ Details

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