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Long-term Debt - Additional Information (Details) - USD ($)			3 Months Ended	9 Months Ended
	Oct. 31, 2026	Aug. 12, 2026	Sep. 30, 2026	Sep. 30, 2026	Nov. 18, 2025
Debt Instrument [Line Items]
Unamortized deferred financing costs			$ 3,600,000	$ 3,600,000
Unamortized original issue discount costs			10,400,000	10,400,000
Amortization expense related to deferred financing costs and original issue discount.			$ 600,000	$ 1,800,000
Zero Cost Interest Rate Collar Agreements One \| Subsequent Event
Debt Instrument [Line Items]
Notional amount	$ 375,000,000
Zero Cost Interest Rate Collar Agreements Two \| Subsequent Event
Debt Instrument [Line Items]
Notional amount	$ 375,000,000
SOFR \| Subsequent Event
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)	5.25%
Floor Rate \| Debt Mature in February 2029 \| Subsequent Event
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)	4.25%
Floor Rate \| Debt Mature in February 2030 \| Subsequent Event
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)	4.30%
Credit Agreement
Debt Instrument [Line Items]
Debt instrument remaining cash flows original terms percentage			10.00%	10.00%
Credit agreement amendment, arranger fees and recognized				$ 2,600,000
Write off deferred financing costs with extinguished portion of the debt				$ 500,000
Credit Agreement \| Senior Secured Term Loan A Facility
Debt Instrument [Line Items]
Debt instrument remaining cash flows amended terms percentage			10.00%	10.00%
Credit Agreement \| Senior Secured Term Loan B Facility
Debt Instrument [Line Items]
Debt instrument remaining cash flows amended terms percentage			10.00%	10.00%
Credit Agreement \| JPMorgan Chase Bank, N.A. \| Senior Secured Term Loan A Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Aggregate principal amount		$ 745,300,000
Line of credit facility maturity date		Feb. 12, 2031
Interest rate added to base rate (as a percent)				0.75%
Credit Agreement \| JPMorgan Chase Bank, N.A. \| Senior Secured Term Loan B Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Aggregate principal amount		$ 773,100,000
Line of credit facility maturity date		Aug. 12, 2031
Interest rate added to base rate (as a percent)				0.50%
Credit Agreement \| SOFR \| JPMorgan Chase Bank, N.A. \| Senior Secured Term Loan A Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)				2.25%
Credit Agreement \| Alternate Base Rate \| JPMorgan Chase Bank, N.A. \| Senior Secured Term Loan A Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)				1.25%
Credit Agreement \| Maximum \| SOFR \| Senior Secured Term Loan A Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)				2.25%
Credit Agreement \| Maximum \| Alternate Base Rate \| Senior Secured Term Loan A Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)				1.25%
Credit Agreement \| Minimum
Debt Instrument [Line Items]
Debt instrument remaining cash flows amended terms percentage			10.00%	10.00%
Credit Agreement \| Minimum \| SOFR \| Senior Secured Term Loan A Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)				1.75%
Credit Agreement \| Minimum \| Alternate Base Rate \| Senior Secured Term Loan A Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)				0.75%
Bridge Term Loan Credit Agreement \| JPMorgan Chase Bank, N.A. \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Aggregate principal amount					$ 1,500,000,000
Financing costs			$ 0	$ 7,400,000