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Long-term Debt - Additional Information (Details) - USD ($)		3 Months Ended	6 Months Ended
	Feb. 12, 2026	Jun. 30, 2026	Jun. 30, 2026	Nov. 18, 2025
Debt Instrument [Line Items]
Unamortized deferred financing costs		$ 3,900,000	$ 3,900,000
Unamortized original issue discount costs		11,400,000	11,400,000
Amortization expense related to deferred financing costs and original issue discount.		800,000	1,200,000
Credit Agreement \| JPMorgan Chase Bank, N.A. \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Aggregate principal amount	$ 1,525,000,000
Credit Agreement \| JPMorgan Chase Bank, N.A. \| Senior Secured Term Loan A Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Aggregate principal amount	$ 750,000,000
Line of credit facility maturity date	Feb. 12, 2031
Credit Agreement \| JPMorgan Chase Bank, N.A. \| Senior Secured Term Loan B Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Aggregate principal amount	$ 775,000,000
Line of credit facility maturity date	Aug. 12, 2031
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)	2.75%
Credit Agreement \| SOFR \| JPMorgan Chase Bank, N.A. \| Senior Secured Term Loan B Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)	2.75%
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)	1.75%
Credit Agreement \| Alternate Base Rate \| JPMorgan Chase Bank, N.A. \| Senior Secured Term Loan B Facility \| Avadel Pharmaceuticals Plc
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)	1.75%
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		$ 7,400,000	$ 7,400,000