OMIDRIA Royalty Obligation (Details) - DRI $ in Millions	Sep. 30, 2022 USD ($)
Royalty Obligation
Remainder of 2022	$ 1.7
Calendar year 2023	13.0
Calendar year 2024	20.0
Calendar years 2025 through 2028	25.0
Calendar year 2029	26.3
Calendar year 2030	$ 27.5

Amount of royalty obligation to be paid in next fiscal year following current fiscal year.

No definition available.

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Namespace Prefix:	omer_
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- Definition

Amount of royalty obligation to be paid in Eighth fiscal year following current fiscal year.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Amount of royalty obligation to be paid in seventh fiscal year following current fiscal year.

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No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Amount of royalty obligation to be paid in third fiscal year through sixth fiscal year following current fiscal year.

+ References

No definition available.

+ Details

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Namespace Prefix:	omer_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of royalty obligation to be paid in second fiscal year following current fiscal year.

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No definition available.

+ Details

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

- Definition

Amount of royalty obligation to be paid in remainder of current fiscal year.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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Balance Type:
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