Planned Acquisition of IPG by Omnicom (Details)	3 Months Ended
Mar. 31, 2025 USD ($)
Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]
Conversion of Stock, Amount Converted	$ 0.344
Percentage of Voting Interests in Post-Merger entity - Omnicom Shareholders	60.60%
Percentage of Voting Interests in Post-Merger entity - IPG Shareholders	39.40%
Gain (Loss) on Contract Termination	$ 439,000,000.0
Business Combination, Transaction Cost, Excluding Separately Recognized Transaction	$ 4,800,000

Percentage of Voting Interests in Post-Merger entity - IPG Shareholders

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- Definition

Percentage of Voting Interests in Post-Merger entity - Omnicom Shareholders

+ References

No definition available.

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- Definition

Amount of transaction cost incurred to effect business combination. Excludes separately recognized transaction and indirect cost.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
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The value of the stock converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

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