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Threshold period of specified consecutive trading days within which the maximum product of the closing sale price of shares of the entity's common stock and the applicable conversion rate for such trading day triggers the conversion feature.

No definition available.

Name:	omer_DebtInstrumentConvertibleThresholdConsecutiveTradingDayPeriod
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Represents the maximum product of the closing sale price of shares of the entity's common stock and the applicable conversion rate for such trading day.

No definition available.

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Represents the denominator amount used in the calculation of convertible debt.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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.

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	num:perShareItemType
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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

No definition available.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

No definition available.

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Data Type:	num:percentItemType
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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

No definition available.

Name:	us-gaap_DebtInstrumentConvertibleThresholdTradingDays
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Data Type:	xbrli:integerItemType
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Period Type:	duration

Contractual interest rate for funds borrowed, under the debt agreement.

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Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_DebtInstrumentLineItems
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Name:	srt_RangeAxis=srt_MinimumMember
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