Convertible Securities (Details) (USD $)	9 Months Ended
Sep. 30, 2011
Debt, Credit Arrangements and Preferred Stock [Abstract]
Convertible notes, Conversion ratio before adjustment for dividends	80.5153
Convertible notes, Conversion ratio	81.3289
Convertible notes, Conversion price before adjustment for dividends	$ 12.42
Convertible notes, Conversion price	$ 12.30
Convertible preferred stock stated interest rate	5.25%
Convertible preferred stock, Conversion ratio before adjustment for dividends	73.1904
Convertible preferred stock, Conversion ratio	74.4500
Convertible preferred stock, Conversion price before adjustment for dividends	$ 13.66
Convertible preferred stock, Conversion price	$ 13.43

The price per share of the conversion feature embedded in the convertible preferred stock instrument.

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Period Type:	instant

- Definition

The ratio applied to the preferred stock for purposes of determining the number of shares of common stock into which the preferred stock will be converted.

+ Details

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Period Type:	duration

- Definition

Prior to the adjustment as a result of the cumulative effect of cash dividends on common stock, the previous ratio applied to the preferred stock for purposes of determining the number of shares of common stock into which the preferred stock will be converted.

+ Details

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- Definition

Interest rate stated in convertible preferred stock agreement.

+ Details

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Period Type:	instant

- Definition

Before the adjustment for payment of cash dividends, the price per share of the conversion feature embedded in the convertible preferred stock instrument.

+ Details

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- Definition

Debt, Credit Arrangements and Preferred Stock [Abstract]

+ Details

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- Definition

Prior to the adjustment as a result of the cumulative effect of cash dividends on common stock, the previous ratio applied to the debt for purposes of determining the number of shares of the equity security into which the debt will be converted.

+ Details

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Namespace Prefix:	ipg
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Before the adjustment for payment of cash dividends, the price per share of the conversion feature embedded in the debt instrument.

+ Details

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Namespace Prefix:	ipg
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Period Type:	instant

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number APB14-1

-Paragraph 32

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

The ratio applied to the debt for purposes of determining the number of shares of the equity security into which the debt will be converted.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(5))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Conversion Rate

-URI http://asc.fasb.org/extlink&oid=6509012

+ Details

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