Collaborative Arrangement, Minimum Royalty Payment Eliminated

No definition available.

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

- Definition

The percentage of supplemental royalty based on net sales.

+ References

No definition available.

+ Details

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

- Definition

Represents the royalty payment as percentage of annual net sales.

+ References

No definition available.

+ Details

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

- Definition

Represents the royalty payment as percentage of annual net sales after specific period.

+ References

No definition available.

+ Details

Name:	coll_CollaborativeArrangementRoyaltyPaymentAsPercentageOfAnnualNetSalesAfterSpecificPeriod
Namespace Prefix:	coll_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Collaborative Arrangement, Royalty Payment Limit

+ References

No definition available.

+ Details

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

- Definition

Collaborative Arrangement, Royalty Payment Limit After Specific Period

+ References

No definition available.

+ Details

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

- Definition

Collaborative Arrangement, Supplemental Royalty Payment Based on Net Sales

+ References

No definition available.

+ Details

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

- Definition

Collaborative Arrangement, Termination Fee

+ References

No definition available.

+ Details

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

- Definition

License Agreements [Line Items]

+ References

No definition available.

+ Details

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Namespace Prefix:	coll_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	coll_MinimumQuarterlyRoyaltyPaymentsLiability
Namespace Prefix:	coll_
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

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

- Definition

The amount of cash transferred for inventory as per agreement.

+ References

No definition available.

+ Details

Name:	coll_PaymentForInventory
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

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

- Definition

Sales threshold where supplemental royalty payment is due

+ 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
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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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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-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

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License Agreements (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended		9 Months Ended
	Jan. 09, 2018	Nov. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
License Agreements [Line Items]
Cost of product revenues			$ 46,754	$ 46,007	$ 144,572	$ 135,951
Annual net sales			$ 72,942	$ 70,176	$ 222,498	$ 206,986
Exercise price of warrant		$ 19.20
Nucynta Commercialization Agreement \| Assertio
License Agreements [Line Items]
Cost of product revenues	$ 10,000
Annual net sales	135,000
Nucynta Commercialization Agreement \| Nucynta \| Assertio
License Agreements [Line Items]
Payment for inventory	6,223
Reimbursement for prepaid expenses	1,987
Liability relating to sales	22,660
Variable royalty payment based on net sales	233,000
Quarterly royalty payable	$ 33,750
Nucynta Commercialization Agreement \| Nucynta \| Assertio \| Sales Royalty Structure 1 [member]
License Agreements [Line Items]
Royalty payment as percentage of annual net sales on and after January 1, 2022		58.00%
Nucynta Commercialization Agreement \| Nucynta \| Assertio \| Sales Royalty Structure 2 [member]
License Agreements [Line Items]
Royalty payment as percentage of annual net sales on and after January 1, 2022		25.00%
Nucynta Commercialization Agreement \| Nucynta \| Assertio \| Sales Royalty Structure 3 [member]
License Agreements [Line Items]
Royalty payment as percentage of annual net sales on and after January 1, 2022		17.50%
Royalty payment limit on and after January 1, 2022		$ 258,000
Nucynta Commercialization Agreement \| Nucynta \| Assertio \| Minimum \| Sales Royalty Structure 2 [member]
License Agreements [Line Items]
Royalty payment limit on and after January 1, 2022		233,000
Nucynta Commercialization Agreement \| Nucynta \| Assertio \| Maximum \| Sales Royalty Structure 1 [member]
License Agreements [Line Items]
Royalty payment limit on and after January 1, 2022		233,000
Nucynta Commercialization Agreement \| Nucynta \| Assertio \| Maximum \| Sales Royalty Structure 2 [member]
License Agreements [Line Items]
Royalty payment limit on and after January 1, 2022		$ 258,000
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
License Agreements [Line Items]
Minimum royalty payment eliminated		$ 135,000
Third Amendment to the Commercialization Agreement \| Nucynta \| 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 \| 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 \| Assertio
License Agreements [Line Items]
Termination fee owed if Company terminates		$ 5,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Sales Royalty Structure 1 [member]
License Agreements [Line Items]
Royalty payment as percentage of annual net sales between January 1, 2019 and December 31, 2021		65.00%
Royalty payment limit between January 1, 2019 and December 31, 2021		$ 180,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Sales Royalty Structure 2 [member]
License Agreements [Line Items]
Royalty payment as percentage of annual net sales between January 1, 2019 and December 31, 2021		14.00%
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Sales Royalty Structure 3 [member]
License Agreements [Line Items]
Royalty payment as percentage of annual net sales between January 1, 2019 and December 31, 2021		58.00%
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Sales Royalty Structure 4 [member]
License Agreements [Line Items]
Royalty payment as percentage of annual net sales between January 1, 2019 and December 31, 2021		20.00%
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Sales Royalty Structure 5 [member]
License Agreements [Line Items]
Royalty payment as percentage of annual net sales between January 1, 2019 and December 31, 2021		15.00%
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Minimum \| Sales Royalty Structure 2 [member]
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021		$ 180,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Minimum \| Sales Royalty Structure 3 [member]
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021		210,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Minimum \| Sales Royalty Structure 4 [member]
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021		233,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Minimum \| Sales Royalty Structure 5 [member]
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021		258,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Minimum \| Sales Royalty Structure 6 [member]
License Agreements [Line Items]
Sales threshold where supplemental royalty payment is due		$ 180,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Maximum
License Agreements [Line Items]
Percentage of supplemental royalty based on net sales		4.90%
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Maximum \| Sales Royalty Structure 2 [member]
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021		$ 210,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Maximum \| Sales Royalty Structure 3 [member]
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021		233,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Maximum \| Sales Royalty Structure 4 [member]
License Agreements [Line Items]
Royalty payment limit between January 1, 2019 and December 31, 2021		258,000
Third Amendment to the Commercialization Agreement \| Nucynta \| Assertio \| Maximum \| Sales Royalty Structure 6 [member]
License Agreements [Line Items]
Sales threshold where supplemental royalty payment is due		$ 243,000