Amount of purchase price for asset purchase agreement.

No definition available.

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- Definition

The amount of guaranteed royalty payable as per the collaborative agreement.

+ References

No definition available.

+ Details

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- Definition

Collaborative Arrangement, Minimum Royalty Payment Eliminated

+ References

No definition available.

+ Details

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- Definition

Represents the royalty payment as percentage of annual net sales.

+ References

No definition available.

+ Details

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- Definition

Collaborative Arrangement, Royalty Payment Limit

+ References

No definition available.

+ Details

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- Definition

Collaborative Arrangement, Supplemental Royalty Payment Based on Net Sales

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

License Agreements [Line Items]

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Definition

The amount of minimum royalty should be paid for each quarter.

+ References

No definition available.

+ Details

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

- Definition

Net Sales Threshold Upon Which Counterparty can Terminate Without Penalty

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The amount of cash transferred for inventory as per agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	coll_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The amount of prepaid expenses reimbursed.

+ References

No definition available.

+ Details

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Namespace Prefix:	coll_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 55
-Paragraph 27
-URI http://asc.fasb.org/extlink&oid=118944142&loc=SL49130611-203046-203046

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Balance Type:	credit
Period Type:	instant

- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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License Agreements (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended	3 Months Ended
	Feb. 06, 2020	Jan. 09, 2018	Nov. 30, 2018	Mar. 31, 2020	Mar. 31, 2019
License Agreements [Line Items]
License fee				$ 37,524	$ 49,164
Annual net sales				76,511	74,516
Nucynta Products
License Agreements [Line Items]
Annual net sales				$ 45,004	$ 49,382
Nucynta Commercialization Agreement \| Assertio
License Agreements [Line Items]
License fee		$ 10,000
Nucynta Commercialization Agreement \| Nucynta Products \| Assertio
License Agreements [Line Items]
Payment for inventory		6,223
Reimbursement for prepaid expenses		1,987
Liability relating to sales		22,660
Annual net sales		135,000
Quarterly royalty payable		33,750
Base annual net sales for variable royalty		$ 233,000
Third Amendment to the Commercialization Agreement
License Agreements [Line Items]
Number of shares that can be purchased			1,041,667
Exercise price of warrant			$ 19.20
Third Amendment to the Commercialization Agreement \| Nucynta Products
License Agreements [Line Items]
Minimum royalty payment eliminated			$ 135,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Maximum \| Any 12-month period through January 1, 2022
License Agreements [Line Items]
Net sales limit upon which Counterparty can terminate without penalty			180,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Maximum \| Any 12-month period commencing on January 1, 2022
License Agreements [Line Items]
Net sales limit upon which Counterparty can terminate without penalty			$ 170,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Sales Royalty Structure 1
License Agreements [Line Items]
Royalty payment as percentage of annual net sales			65.00%
Royalty payment limit between January 1, 2019 and December 31, 2021			$ 180,000
Collaborative Arrangement, Royalty Payment Limit			$ 180,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Sales Royalty Structure 2
License Agreements [Line Items]
Royalty payment as percentage of annual net sales			14.00%
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Sales Royalty Structure 3
License Agreements [Line Items]
Royalty payment as percentage of annual net sales			58.00%
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Sales Royalty Structure 4
License Agreements [Line Items]
Royalty payment as percentage of annual net sales			20.00%
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Sales Royalty Structure 5
License Agreements [Line Items]
Royalty payment as percentage of annual net sales			15.00%
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| prior to January 1, 2022
License Agreements [Line Items]
Royalty payment as percentage of annual net sales			14.00%
Royalty payment limit between January 1, 2019 and December 31, 2021			$ 34,000
Collaborative Arrangement, Royalty Payment Limit			34,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Minimum \| Sales Royalty Structure 2
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021			180,000
Collaborative Arrangement, Royalty Payment Limit			180,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Minimum \| Sales Royalty Structure 3
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021			210,000
Collaborative Arrangement, Royalty Payment Limit			210,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Minimum \| Sales Royalty Structure 4
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021			233,000
Collaborative Arrangement, Royalty Payment Limit			233,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Minimum \| Sales Royalty Structure 5
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021			258,000
Collaborative Arrangement, Royalty Payment Limit			258,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Minimum \| prior to January 1, 2022
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021			180,000
Collaborative Arrangement, Royalty Payment Limit			180,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Maximum \| Sales Royalty Structure 2
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021			210,000
Collaborative Arrangement, Royalty Payment Limit			210,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Maximum \| Sales Royalty Structure 3
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021			233,000
Collaborative Arrangement, Royalty Payment Limit			233,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Maximum \| Sales Royalty Structure 4
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021			258,000
Collaborative Arrangement, Royalty Payment Limit			258,000
Third Amendment to the Commercialization Agreement \| Nucynta Products \| Assertio \| Maximum \| prior to January 1, 2022
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021			243,000
Collaborative Arrangement, Royalty Payment Limit			$ 243,000
Nucynta Purchase Agreement \| Nucynta Products \| Assertio
License Agreements [Line Items]
Royalty payment as percentage of annual net sales	14.00%
Aggregate purchase price	$ 375,000
Guaranteed royalty	34,000
Nucynta Purchase Agreement \| Nucynta Products \| Assertio \| Minimum
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021	180,000
Collaborative Arrangement, Royalty Payment Limit	180,000
Nucynta Purchase Agreement \| Nucynta Products \| Assertio \| Maximum
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021	243,000
Collaborative Arrangement, Royalty Payment Limit	$ 243,000