Segment Reporting - Schedule of Segment Reporting Information (Details) - USD ($) $ in Thousands		3 Months Ended						9 Months Ended
		Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting, Asset Reconciling Item [Line Items]
Total revenues		$ 192,103			$ 175,689			$ 507,380	$ 487,658
Cost of goods sold	[1]	18,965			17,583			51,555	51,808
Total research and development expenses		29,366			29,036			78,408	80,149
Net earnings (loss)		(45,117)	$ 22,499	$ (11,827)	38,497	$ 19,916	$ 124	(34,445)	58,537
Reportable Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Total revenues		192,103			175,689			507,380	487,658
Cost of goods sold		18,965			17,583			51,555	51,808
Selling expenses		58,386			38,082			145,398	116,190
Marketing expenses		18,672			16,247			60,068	56,510
General and administrative expenses		33,114			15,424			86,833	69,473
Acquisition-related expenses		69,506			0			70,874	0
Total external development program expenses		16,061			19,518			44,630	51,077
Internal employee-related expenses		13,305			9,518			33,778	29,072
Total research and development expenses		29,366			29,036			78,408	80,149
Other segment items		9,211			20,820			48,689	54,991
Net earnings (loss)		(45,117)			38,497			(34,445)	58,537
Reportable Segment | ONAPGO
Segment Reporting, Asset Reconciling Item [Line Items]
Total external development program expenses		352			71			1,613	1,164
Reportable Segment | SPN-820
Segment Reporting, Asset Reconciling Item [Line Items]
Total external development program expenses		1,111			6,668			8,073	20,010
Reportable Segment | SPN-817
Segment Reporting, Asset Reconciling Item [Line Items]
Total external development program expenses		4,872			2,815			11,889	5,835
Reportable Segment | Qelbree
Segment Reporting, Asset Reconciling Item [Line Items]
Total external development program expenses		3,168			5,621			9,805	11,552
Reportable Segment | ZURZUVAE
Segment Reporting, Asset Reconciling Item [Line Items]
Total external development program expenses		1,385			0			1,385	0
Reportable Segment | Early stage programs and other expenses
Segment Reporting, Asset Reconciling Item [Line Items]
Total external development program expenses		$ 5,173			$ 4,343			$ 11,865	$ 12,516

[1] Excludes amortization of intangible assets