Represents the notice period required to be served before the termination of the agreement.

No definition available.

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- Definition

Represents the know-how patent royalty as a percentage of net sales under the collaborative agreements.

+ References

No definition available.

+ Details

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- Definition

Collaborative arrangement know how royalty rate resets.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of milestone payment entitled to be received upon the acceptance of NDA by the FDA, under the collaborative arrangement.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of milestone payment entitled to be received upon the approval of NDA by the FDA, under the collaborative arrangement.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of milestone payment entitled to be received upon the first commercial sale, under the collaborative arrangement.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of milestone payment entitled to be received upon the initiation of phase 3 clinical trial, under the collaborative arrangement.

+ References

No definition available.

+ Details

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- Definition

Represents the aggregate worldwide net sales tied to know-how royalty under the collaborative agreements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the patent royalty as a percentage of net sales under the collaborative agreements.

+ References

No definition available.

+ Details

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- Definition

Collaborative arrangement payment received upon initiation of phase three clinical trial.

+ References

No definition available.

+ Details

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- Definition

Percentage of total annual requirement of product that can be obtained from second source manufacturer under the collaborative agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the period after the date of the first commercial sale of the product in a particular country that the agreement will expire.

+ References

No definition available.

+ Details

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- Definition

Represents the period for resolving default or breach after the receipt of notice for termination of agreement.

+ References

No definition available.

+ Details

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- Definition

Represents royalty as a percentage of net sales under the collaborative agreements.

+ References

No definition available.

+ Details

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- Definition

Represents royalty rate upon termination of related agreement.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Definition

Maximum percentage of product supplies on net sales.

+ References

No definition available.

+ Details

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Namespace Prefix:	alks_
Data Type:	num:percentItemType
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- Definition

Represents the number of license agreements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Percentage of net sales in royalty payment.

+ References

No definition available.

+ Details

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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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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)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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Collaborative Arrangements - Significant collaborative arrangements (Details)	1 Months Ended					12 Months Ended
	Dec. 31, 2019 USD ($)	Nov. 30, 2019 USD ($)	Oct. 31, 2019	Jun. 30, 2018 USD ($)	Nov. 30, 2017 USD ($)	Dec. 31, 2019 USD ($) Agreement	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Cash payments received						$ 1,170,947,000	$ 1,094,274,000	$ 903,374,000
VUMERITY
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of net sales in royalty payment						15.00%
Maximum percentage of product supplies on net sales			100.00%
Biogen
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payment received upon the initiation of phase 3 clinical trial					$ 50,000,000.0
Biogen \| License
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Cash payments received	$ 5,000,000.0	$ 150,000,000.0		$ 50,000,000.0	$ 28,000,000.0
Percentage of net sales in royalty payment						15.00%
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Patent royalty rate (as a percent)						1.50%
Know-how royalty rate resets (as a percent)						3.50%
Period after the date of the first commercial sale of the product for license expiration						15 years
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION \| Net sales of below $250.0 million
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Know-how royalty rate (as a percent)						3.50%
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION \| Net sales between $250.0 million and 500.0 million
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Know-how royalty rate (as a percent)						5.50%
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION \| Net sales greater than $500.0 million
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Know-how royalty rate (as a percent)						7.50%
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION \| Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Royalty rate (as a percent)						5.00%
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION \| Minimum \| Net sales between $250.0 million and 500.0 million
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Aggregate worldwide net sales						$ 250,000,000
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION \| Minimum \| Net sales greater than $500.0 million
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Aggregate worldwide net sales						$ 500,000,000
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Royalty rate (as a percent)						9.00%
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION \| Maximum \| Net sales of below $250.0 million
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Aggregate worldwide net sales						$ 250,000,000
License agreement \| Janssen \| INVEGA SUSTENNA/XEPLION \| Maximum \| Net sales between $250.0 million and 500.0 million
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Aggregate worldwide net sales						$ 500,000,000
License agreement \| Janssen \| RISPERDAL CONSTA
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Royalty rate (as a percent)						2.50%
Period after the date of the first commercial sale of the product for license expiration						15 years
Number of license agreements \| Agreement						2
Notice period required to be given before termination of agreement						30 days
Period for resolving default or breach after the receipt of notice for termination of agreement						90 days
License agreement \| Acorda
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment entitled to be received upon the initiation of phase 3 clinical trial	1,000,000.0					$ 1,000,000.0
Milestone payment entitled to be received upon the acceptance of NDA by the FDA	1,000,000.0					1,000,000.0
Milestone payment entitled to be received upon the approval of NDA by the FDA	1,500,000					1,500,000
Milestone payment entitled to be received upon the first commercial sale	$ 1,500,000					$ 1,500,000
License agreement \| Acorda \| AMPYRA/ FAMPYRA
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Royalty rate (as a percent)						10.00%
Notice period required to be given before termination of agreement						90 days
Manufacturing and supply agreement \| Janssen \| RISPERDAL CONSTA
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Period after the date of the first commercial sale of the product for license expiration						60 days
Notice period required to be given before termination of agreement						6 months
Manufacturing and supply agreement \| Janssen \| RISPERDAL CONSTA \| Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Royalty rate (as a percent)						7.50%
Royalty rate upon termination of manufacturing and supply agreement (as a percent)						2.50%
Manufacturing and supply agreement \| Janssen \| RISPERDAL CONSTA \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Royalty rate upon termination of manufacturing and supply agreement (as a percent)						5.00%
Manufacturing and supply agreement \| Acorda \| AMPYRA/ FAMPYRA
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Royalty rate (as a percent)						8.00%
Notice period required to be given before termination of agreement						12 months
Manufacturing and supply agreement \| Acorda \| AMPYRA/ FAMPYRA \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of total annual requirement of product that can be obtained from second source manufacturer						25.00%