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Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Amount Expected to be Recognized in Year One

No definition available.

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Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Amount Expected to be Recognized in Year Three

No definition available.

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Namespace Prefix:	omg_
Data Type:	xbrli:monetaryItemType
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Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Amount Expected to be Recognized in Year Two

No definition available.

Name:	omg_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedAmountExpectedToBeRecognizedInYearTwo
Namespace Prefix:	omg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph h

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901