Agreement Covenant, Maximum Indemnification Cap

No definition available.

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- Definition

Agreement Covenant, Rate of Return

+ References

No definition available.

+ Details

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- Definition

Milestone payment receivable under purchase agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Royalty Revenue, Milestone Amount, Achieved In Two Consecutive Fiscal Quarters

+ References

No definition available.

+ Details

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- Definition

Royalty Revenue, Milestone Period

+ References

No definition available.

+ Details

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- Definition

Royalty Revenue, Percent Received Upon Milestone Payment

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Royalty Revenue, Percent Received Upon Milestone Payment, Without Commercialization

+ References

No definition available.

+ Details

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- Definition

Royalty Revenue, Percent Received Without Milestone Payment

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Royalty Revenue, Percent Received Without Milestone Payment, Without Commercialization

+ References

No definition available.

+ Details

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Namespace Prefix:	opnt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Royalty Revenue, Potential Revenue

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

[Line Items] for Schedule of Royalties [Table]

+ References

No definition available.

+ Details

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- Definition

Upfront purchase price received under purchase agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(4))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cash received for royalties during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

+ Details

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- Details

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- Details

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- Details

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Sale of Royalties (Details) - USD ($)				1 Months Ended	12 Months Ended
Sale of Royalties (Details) - USD ($)	Dec. 31, 2017	Aug. 10, 2017	Dec. 13, 2016	Dec. 31, 2016	Sep. 30, 2017	Jul. 31, 2017	Jul. 31, 2016
Schedule of Royalties [Line Items]
Accounts receivable	$ 11,696,676					$ 3,750,000	$ 312,498
SWK Purchase Agreement
Schedule of Royalties [Line Items]
Upfront purchase price received under purchase agreement			$ 13,750,000			13,750,000
Legal fees			40,000			40,000
Milestone payment receivable under purchase agreement			$ 3,750,000			3,750,000
Agreement covenant, rate of return			12.00%
Agreement covenant, maximum indemnification cap			150.00%
Proceeds from royalties received		$ 3,750,000		$ 13,710,000		17,460,000
Accounts receivable	$ 11,696,676					$ 3,750,000
SWK Purchase Agreement \| Minimum
Schedule of Royalties [Line Items]
Cumulative net sales milestone					$ 25,000,000
SWK Purchase Agreement \| SWK Funding LLC
Schedule of Royalties [Line Items]
Royalty and licensing revenue			$ 26,250,000
Royalty revenue, percent received upon milestone payment	10.00%		10.00%
Milestone period			6 years
Percent received upon milestone payment, without commercialization			5.00%
Percent received without milestone payment			7.86%
Percent received without milestone payment, without commercialization			3.93%
SWK Purchase Agreement \| SWK Funding LLC \| Maximum
Schedule of Royalties [Line Items]
Royalty and licensing revenue			$ 20,625,000