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The proceeds from the transfer of inventory per the agreement.

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The upfront payment received on closing of the transaction.

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Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Represent percentage of revenue remaining performance obligation.

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The total minimum royalties that will be earned per the agreement.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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REVENUE - Commercialization Agreement with Collegium (Details)	1 Months Ended	3 Months Ended			6 Months Ended	9 Months Ended		12 Months Ended
	Jan. 31, 2018 USD ($) performance_obligation	Sep. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2018 USD ($)
Collaboration and License Agreements
Total revenues		$ 77,493,000		$ 95,413,000		$ 269,171,000	$ 286,317,000
Royalties and milestones
Collaboration and License Agreements
Total revenues		$ 20,277,000		$ 209,000		$ 25,784,000	$ 596,000
Collegium Pharmaceutical Inc
Collaboration and License Agreements
Contract liability	$ 10,000,000
Commercialization agreement, net \| NUCYNTA products \| Collegium Pharmaceutical Inc
Collaboration and License Agreements
Proceeds from transfer of inventory	$ 6,200,000
Number of performance obligations (performance obligation) \| performance_obligation	3
Transaction price	$ 553,200,000
Total minimum royalties	537,000,000
Upfront payment	10,000,000
Termination fee Collegium could pay	25,000,000
Equal quarterly installments of annual minimum royalty payable	33,800,000
Percentage of cash receipts in lockbox account are swept to bank accounts up to the minimum cash royalty amount for the quarter		35.00%			35.00%	35.00%
Minimum cash royalty amounts			$ 30,800,000		$ 33,800,000
Threshold period for remitting the remaining royalty payment						45 days
Amount received						$ 98,300,000
Commercialization agreement, net \| NUCYNTA products \| Grunenthal \| Royalties and milestones
Collaboration and License Agreements
Royalty revenue recognized		$ 3,700,000
Commercialization agreement, net \| Forecast \| NUCYNTA products \| Collegium Pharmaceutical Inc
Collaboration and License Agreements
Minimum annual royalties								$ 135,000,000	$ 135,000,000	$ 132,000,000
Performance Obligation Transfer Of Finished Goods \| NUCYNTA products \| Collegium Pharmaceutical Inc
Collaboration and License Agreements
Transaction price	55,700,000
Performance Obligation Commercialize And Facilitation Services \| Collegium Pharmaceutical Inc
Collaboration and License Agreements
Total revenues		$ 27,800,000				142,800,000
Performance Obligation Commercialize And Facilitation Services \| NUCYNTA products \| Collegium Pharmaceutical Inc
Collaboration and License Agreements
Transaction price	$ 497,500,000
Total revenues						$ 87,100,000