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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of warrants outstanding and currently exercisable.

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No definition available.

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Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

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No definition available.

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Number of warrants or rights outstanding.

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Face amount or stated value per share of common stock.

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Unrecognized cost of unvested share-based compensation awards.

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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- Definition

Number of shares of capital stock issued (purchased by employees) in connection with an employee stock ownership plan.

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- Definition

Amount of stock repurchase plan authorized.

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No definition available.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased during the period and are being held in treasury.

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The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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Equity Instruments and Share-Based Compensation (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2018	Mar. 12, 2018	Feb. 23, 2018	Feb. 12, 2018	Jan. 01, 2018	Mar. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ordinary shares, shares authorized (in shares)	500,000,000	500,000,000
Ordinary shares, nominal value (in usd or euro per share)	$ 0.01	$ 0.01
Ordinary shares, shares issued (in shares)	42,927,000	42,720,000
Ordinary shares, shares outstanding (in shares)	37,520,000	37,313,000
Preferred shares, shares authorized (in shares)	50,000,000	50,000,000
Preferred shares, nominal value (in usd per share)	$ 0.01	$ 0.01
Preferred shares, shares outstanding (in shares)	0	0
Authorized repurchase amount				$ 7,000,000			$ 18,000,000		$ 25,000,000
Stock repurchase program, remaining authorized repurchase amount				$ 50,000,000
Share repurchases (in shares)	5,407,000
Share repurchases	$ (49,998,000)	$ (49,998,000)
Unrecognized compensation expense	$ 2,695,000
Weighted average period for unrecognized expense (in years)	2 years 4 months 13 days
Aggregate intrinsic value of options exercised	$ 572,000	$ 0	$ 1,161,000
Grant date fair value of options granted (in usd per share)	$ 1.24	$ 3.60	$ 5.20
Number of securities called by each warrant (in shares)	1
Additional warrants outstanding								3,300,000
Warrant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	1 year
Expiration period (in years)	4 years
Aggregate intrinsic value of warrants exercised	$ 0	$ 0	$ 0
Granted (in shares)	0	0	0
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee share purchase plan share issuance (in shares)	54,000	25,000
Free Share Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)		3 years
Granted (in shares)	251,000
Weighted average grant fair value of free share awards	$ 2.47	$ 5.87	$ 8.95
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	565,716,000
Vesting period (in years)	4 years
Expiration period (in years)	10 years
2017 Avadel Employee Share Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ordinary shares, nominal value (in usd or euro per share)	$ 0.01
Shares available for issuance under ESPP	1,000,000
Purchase price of common stock, percentage	85.00%
Eclat Pharmaceuticals
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities called by each warrant (in shares)						2,200,000
Remaining warrants outstanding expired					1,100,000
2/3 vesting at second anniversary of grant date \| Free Share Award, Grants during 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	67.00%
1/3 vesting at third anniversary of grant date \| Free Share Award, Grants during 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
1/3 vesting at third anniversary of grant date \| Free Share Award, Grants beginning 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
1/3 vesting at first anniversary of grant date \| Free Share Award, Grants beginning 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
1/3 vesting at second anniversary of grant date \| Free Share Award, Grants beginning 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%