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The amount of intellectual property payment due upon achievement of developmental milestones.

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The amount of intellectual property payment due upon achievement of preclinical milestones.

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The amount of intellectual property payment due upon achievement of regulatory milestones.

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The amount of intellectual property payment due upon achievement of sales milestones.

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License agreement additional milestone payments due.

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License agreement final payment paid.

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License agreement maximum additional milestone payments due.

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License agreement milestone payments Due.

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License agreement milestone payments paid.

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The amount of preclinical milestone payments recognized under the license agreement.

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Represents information pertaining to license agreement upfront non-refundable fees paid.

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Line items represent License and asset purchase agreements.

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Licensing agreement milestone fees

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for royalties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer.

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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.

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LICENSE AGREEMENTS AND ASSET PURCHASE AGREEMENTS (Details) - USD ($) $ in Thousands	1 Months Ended								3 Months Ended
	Mar. 31, 2023	Jul. 31, 2022	Mar. 31, 2022	Aug. 31, 2021	Jan. 31, 2021	Oct. 31, 2020	Nov. 30, 2019	Aug. 31, 2019	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Feb. 28, 2019
License Agreements and Asset Purchase Agreements
Cost of product sold									$ 27,484	$ 20,780
Accrued Sales Based Trademark and Royalties									24,738		$ 40,419
All Countries Excluding Greater China \| HBS-102 \| Asset Purchase Agreement with ConSynance Therapeutics
License Agreements and Asset Purchase Agreements
Consideration transferred				$ 3,500
Payment for intellectual property upon preclinical milestones				1,000
Payment for intellectual property upon developmental milestones				19,000
Payment for intellectual property upon regulatory milestones				44,000
Payment for intellectual property upon sales milestones				$ 110,000
All Countries Excluding Greater China \| HBS-102 \| Asset Purchase Agreement with ConSynance Therapeutics \| Research and development expense
License Agreements and Asset Purchase Agreements
Payment related to achievement of preclinical milestone.	$ 750,000
Bioprojet
License Agreements and Asset Purchase Agreements
Licensing agreement milestone fees								$ 2,000
License agreement milestone payments paid							$ 75,000	2,000
License agreement, additional milestone payment due								102,000
Bioprojet \| Upon Acceptance by FDA of Pitolisant's
License Agreements and Asset Purchase Agreements
License agreement, milestone payment due												$ 50,000
License agreement, upfront non-refundable licensing fees paid		$ 30,000
License agreement, maximum additional milestone payment due		$ 155,000
Bioprojet \| Upon FDA Approval of WAKIX
License Agreements and Asset Purchase Agreements
License agreement, milestone payment due								77,000
Licensing agreement milestone fees								$ 2,000
License agreement milestone payments paid					$ 100,000	$ 2,000
Bioprojet \| Sales-based, trademark and tiered royalties
License Agreements and Asset Purchase Agreements
Cost of product sold									24,738	$ 19,060
Accrued Sales Based Trademark and Royalties									$ 24,738		$ 40,419
Bioprojet \| United States
License Agreements and Asset Purchase Agreements
Amount of Aggregate Net Sales Attaining			$ 500,000
Bioprojet \| Attaining $500,000 Aggregate Net Sales \| United States \| Upon FDA Approval of WAKIX
License Agreements and Asset Purchase Agreements
Final payment paid			$ 40,000