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Increase (Decrease) in customer advances and other current liabilities

No definition available.

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Data Type:	xbrli:monetaryItemType
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Increase (Decrease) in work in progress and other current assets

No definition available.

Name:	omc_IncreaseDecreaseInWorkInProgressAndOtherCurrentAssets
Namespace Prefix:	omc_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 50
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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Change in recurring obligations of a business that arise from the acquisition of merchandise, materials, supplies and services used in the production and sale of goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- References

No definition available.

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Data Type:	xbrli:stringItemType
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The increase (decrease) during the reporting period in other assets used in operating activities less other operating liabilities used in operating activities not separately disclosed in the statement of cash flows. May include changes in other current assets and liabilities, other noncurrent assets and liabilities, or a combination of other current and noncurrent assets and liabilities.

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The amount of cash paid for interest during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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