Summary of Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2020
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations. Avadel Pharmaceuticals plc (Nasdaq: AVDL) (“Avadel,” the “Company,” “we,” “our,” or “us”) is an emerging biopharmaceutical company. Our lead product candidate, FT218, is an investigational once-nightly formulation of sodium oxybate for the treatment of excessive daytime sleepiness (“EDS”) and cataplexy in narcolepsy patients. FT218 uses our Micropump controlled release drug-delivery technology. We are primarily focused on the development and potential United States (“U.S.”) Food and Drug Administration (“FDA”) approval of FT218. Outside of our lead product candidate, we continue to evaluate opportunities to expand our product portfolio. We were incorporated in Ireland on December 1, 2015 as a private limited company, and re-registered as an Irish public limited company on November 21, 2016. Our headquarters are in Dublin, Ireland and we have operations in St. Louis, Missouri, U.S.
Basis of Presentation	Basis of Presentation. The unaudited condensed consolidated balance sheet as of September 30, 2020, which is derived from the prior year 2019 audited consolidated financial statements, and the interim unaudited condensed consolidated financial statements presented herein, have been prepared in accordance with accounting principles generally accepted in the U.S. (U.S. GAAP), the requirements of Form 10-Q and Article 10 of Regulation S-X and, consequently, do not include all information or footnotes required by U.S. GAAP for complete financial statements or all the disclosures normally made in an Annual Report on Form 10-K. Accordingly, the unaudited condensed consolidated financial statements included herein should be read in conjunction with the audited consolidated financial statements and footnotes included in the Company’s 2019 Annual Report on Form 10-K filed with the SEC on March 16, 2020. The unaudited condensed consolidated financial statements include the accounts of the Company and subsidiaries, and reflect all adjustments (consisting only of normal recurring adjustments) that are, in the opinion of management, necessary for a fair presentation of the Company’s financial position, results of operations and cash flows for the dates and periods presented. All intercompany accounts and transactions have been eliminated. Results for interim periods are not necessarily indicative of the results to be expected during the remainder of the current year or for any future period. On February 6, 2019, our indirect wholly-owned subsidiary, Avadel Specialty Pharmaceuticals, LLC (“Specialty Pharma”), filed a voluntary petition for reorganization under Chapter 11 of the U.S. Code (the “Bankruptcy Code”). in the U.S. District Bankruptcy Court for the District of Delaware (the “Bankruptcy Court”), Case No. 19-10248. Specialty Pharma is operating and managing its business as “debtors-in-possession” under the jurisdiction of the Bankruptcy Court and in accordance with the applicable provisions of the Bankruptcy Code and order of the Bankruptcy Court. As a result of Specialty Pharma’s voluntary bankruptcy filing on February 6, 2019, we no longer controlled the operations of Specialty Pharma; therefore, we deconsolidated Specialty Pharma effective with the bankruptcy filing and the Company recorded its investment in Specialty Pharma under the cost method. See Note 3: Subsidiary Bankruptcy and Deconsolidation. Our results of operations for the period January 1, 2019 through February 6, 2019 include the results of Specialty Pharma prior to its February 6, 2019 voluntary petition for reorganization under Chapter 11 of the U.S. Bankruptcy Code.
Revenue	Revenue. Prior to June 30, 2020, we generated revenue primarily from the sale of pharmaceutical products to customers, which we refer to as the Hospital Products. On June 30, 2020, we sold the Hospital Products. See Note 4: Disposition of the Hospital Products. Product Sales Prior to June 30, 2020, we sold products primarily through wholesalers and considered these wholesalers to be our customers. Revenue from product sales was recognized when the customer obtained control of our product and our performance obligations were met, which occurred typically upon receipt of delivery to the customer. As is customary in the pharmaceutical industry, our gross product sales were subject to a variety of price adjustments in arriving at reported net product sales. These adjustments included estimates for product returns, chargebacks, payment discounts, rebates, and other sales allowances and are estimated when the product is delivered based on analysis of historical data for the product or comparable products, as well as future expectations for such products. For a complete discussion of the accounting for net product revenue, see Note 5: Revenue Recognition. Revenue Recognition Prior to June 30, 2020, we generated revenue primarily from the sale of pharmaceutical products to customers. On June 30, 2020, we sold the Hospital Products. See Note 4: Disposition of the Hospital Products. Product Sales Prior to June 30, 2020, we sold products primarily through wholesalers and considered these wholesalers to be our customers. Revenue from product sales was recognized when the customer obtained control of our product and our performance obligations were met, which occurred typically upon receipt of delivery to the customer. As is customary in the pharmaceutical industry, our gross product sales were subject to a variety of price adjustments in arriving at reported net product sales. These adjustments included estimates for product returns, chargebacks, payment discounts, rebates, and other sales allowances and are estimated when the product is delivered based on analysis of historical data for the product or comparable products, as well as future expectations for such products. Reserves to Reduce Gross Revenues to Net Revenues Revenues from product sales were recorded at the net selling price, which included estimated reserves to reduce gross product sales to net product sales resulting from product returns, chargebacks, payment discounts, rebates, and other sales allowances that are offered within contracts between the Company and its customers and end users. These reserves were based on the amounts earned or to be claimed on the related sales and were classified as reductions of accounts receivable if the amount is payable to the customer, except in the case of the estimated reserve for future expired product returns, which are classified as a liability. The reserves are classified as a liability if the amount is payable to a party other than a customer. Where appropriate, these estimated reserves take into consideration relevant factors such as the Company’s historical experience, current contractual and statutory requirements, specific known market events and trends, industry data and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates to reduce gross selling price to net selling price to which it expects to be entitled based on the terms of its contracts. The actual selling price ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company adjusts these estimates, which would affect net product revenue and earnings in the period such variances become known. Product Returns Consistent with industry practice, the Company maintains a returns policy that generally offers customers a right of return for product that has been purchased from the Company. The Company estimates the amount of product returns and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company currently estimates product return liabilities based on analysis of historical data for the product or comparable products, as well as future expectations for such products and other judgments and analysis. Chargebacks, Discounts and Rebates Chargebacks, discounts and rebates represent the estimated obligations resulting from contractual commitments to sell products to its customers or end users at prices lower than the list prices charged to our wholesale customers. Customers charge the Company for the difference between the gross selling price they pay for the product and the ultimate contractual price agreed to between the Company and these end users. These reserves are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue and accounts receivable. Chargebacks, discounts and rebates are estimated at the time of sale to the customer. Disaggregation of revenue The Company’s source of revenue was from the sale of pharmaceutical products, which are equally affected by the same economic factors as it relates to the nature, amount, timing, and uncertainty of revenue and cash flows. For further detail about the Company’s revenues by product, see Note 19: Revenue by Product. Contract Balances The Company does not recognize revenue in advance of invoicing its customers and therefore has no related contract assets. A receivable is recognized in the period the Company sells its products and when the Company’s right to consideration is unconditional. There were no material deferred contract costs at September 30, 2020. Transaction Price Allocated to the Remaining Performance Obligation For product sales, the Company generally satisfied its performance obligations within the same period the product was delivered. Product sales recognized in the second quarter of 2020 from performance obligations satisfied (or partially satisfied) in previous periods were immaterial. The Company has elected certain of the practical expedients from the disclosure requirement for remaining performance obligations for specific situations in which an entity need not estimate variable consideration to recognize revenue. Accordingly, the Company applies the practical expedient in ASC 606 to its stand-alone contracts and does not disclose information about variable consideration from remaining performance obligations for which the Company recognizes revenue.
Accounts Receivable	Accounts Receivable. Prior to the sale of the Hospital Products on June 30, 2020, accounts receivable are stated at amounts invoiced and certain other gross to net variable consideration deductions. An allowance for credit losses is established based on expected losses. Expected losses are estimated by reviewing individual accounts, considering aging, financial condition of the debtor, payment history, current and forecast economic conditions and other relevant factors. A majority of our accounts receivable are due from four significant customers. As of September 30, 2020, we have collected all of the accounts receivable outstanding as of June 30, 2020.
Newly Issued Accounting Pronouncements	Newly Issued Accounting Standards Recent Accounting Guidance Not Yet Adopted In December 2019, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, as part of its overall simplification initiative to reduce costs and complexity of applying accounting standards while maintaining or improving the usefulness of the information provided to users of financial statements. The FASB’s amendments primarily impact ASC 740, Income Taxes, and may impact both interim and annual reporting periods. ASU 2019-12 will be effective for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years and early adoption is permitted. We are currently evaluating the impact of adopting ASU 2019-12.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2020

Nature of Operations. Avadel Pharmaceuticals plc (Nasdaq: AVDL) (“Avadel,” the “Company,” “we,” “our,” or “us”) is an emerging biopharmaceutical company. Our lead product candidate, FT218, is an investigational once-nightly formulation of sodium oxybate for the treatment of excessive daytime sleepiness (“EDS”) and cataplexy in narcolepsy patients. FT218 uses our Micropump controlled release drug-delivery technology.

We are primarily focused on the development and potential United States (“U.S.”) Food and Drug Administration (“FDA”) approval of FT218. Outside of our lead product candidate, we continue to evaluate opportunities to expand our product portfolio.

We were incorporated in Ireland on December 1, 2015 as a private limited company, and re-registered as an Irish public limited company on November 21, 2016. Our headquarters are in Dublin, Ireland and we have operations in St. Louis, Missouri, U.S.

Basis of Presentation

Basis of Presentation. The unaudited condensed consolidated balance sheet as of September 30, 2020, which is derived from the prior year 2019 audited consolidated financial statements, and the interim unaudited condensed consolidated financial statements presented herein, have been prepared in accordance with accounting principles generally accepted in the U.S. (U.S. GAAP), the requirements of Form 10-Q and Article 10 of Regulation S-X and, consequently, do not include all information or footnotes required by U.S. GAAP for complete financial statements or all the disclosures normally made in an Annual Report on Form 10-K. Accordingly, the unaudited condensed consolidated financial statements included herein should be read in conjunction with the audited consolidated financial statements and footnotes included in the Company’s 2019 Annual Report on Form 10-K filed with the SEC on March 16, 2020.

The unaudited condensed consolidated financial statements include the accounts of the Company and subsidiaries, and reflect all adjustments (consisting only of normal recurring adjustments) that are, in the opinion of management, necessary for a fair presentation of the Company’s financial position, results of operations and cash flows for the dates and periods presented. All intercompany accounts and transactions have been eliminated. Results for interim periods are not necessarily indicative of the results to be expected during the remainder of the current year or for any future period.

On February 6, 2019, our indirect wholly-owned subsidiary, Avadel Specialty Pharmaceuticals, LLC (“Specialty Pharma”), filed a voluntary petition for reorganization under Chapter 11 of the U.S. Code (the “Bankruptcy Code”). in the U.S. District Bankruptcy Court for the District of Delaware (the “Bankruptcy Court”), Case No. 19-10248. Specialty Pharma is operating and managing its business as “debtors-in-possession” under the jurisdiction of the Bankruptcy Court and in accordance with the applicable provisions of the Bankruptcy Code and order of the Bankruptcy Court. As a result of Specialty Pharma’s voluntary bankruptcy filing on February 6, 2019, we no longer controlled the operations of Specialty Pharma; therefore, we deconsolidated Specialty Pharma effective with the bankruptcy filing and the Company recorded its investment in Specialty Pharma under the cost method. See Note 3: Subsidiary Bankruptcy and Deconsolidation. Our results of operations for the period January 1, 2019 through February 6, 2019 include the results of Specialty Pharma prior to its February 6, 2019 voluntary petition for reorganization under Chapter 11 of the U.S. Bankruptcy Code.

Revenue

Revenue. Prior to June 30, 2020, we generated revenue primarily from the sale of pharmaceutical products to customers, which we refer to as the Hospital Products. On June 30, 2020, we sold the Hospital Products. See Note 4: Disposition of the Hospital Products.

Product Sales

Prior to June 30, 2020, we sold products primarily through wholesalers and considered these wholesalers to be our customers. Revenue from product sales was recognized when the customer obtained control of our product and our performance obligations were met, which occurred typically upon receipt of delivery to the customer. As is customary in the pharmaceutical industry, our gross product sales were subject to a variety of price adjustments in arriving at reported net product sales. These adjustments included estimates for product returns, chargebacks, payment discounts, rebates, and other sales allowances and are estimated when the product is delivered based on analysis of historical data for the product or comparable products, as well as future expectations for such products.

For a complete discussion of the accounting for net product revenue, see Note 5: Revenue Recognition.

Revenue Recognition

Prior to June 30, 2020, we generated revenue primarily from the sale of pharmaceutical products to customers. On June 30, 2020, we sold the Hospital Products. See Note 4: Disposition of the Hospital Products.

Product Sales

Reserves to Reduce Gross Revenues to Net Revenues

Revenues from product sales were recorded at the net selling price, which included estimated reserves to reduce gross product sales to net product sales resulting from product returns, chargebacks, payment discounts, rebates, and other sales allowances that are offered within contracts between the Company and its customers and end users. These reserves were based on the amounts earned or to be claimed on the related sales and were classified as reductions of accounts receivable if the amount is payable to the customer, except in the case of the estimated reserve for future expired product returns, which are classified as a liability. The reserves are classified as a liability if the amount is payable to a party other than a customer. Where appropriate, these estimated reserves take into consideration relevant factors such as the Company’s historical experience, current contractual and statutory requirements, specific known market events and trends, industry data and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates to reduce gross selling price to net selling price to which it expects to be entitled based on the terms of its contracts. The actual selling price ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company adjusts these estimates, which would affect net product revenue and earnings in the period such variances become known.

Product Returns

Consistent with industry practice, the Company maintains a returns policy that generally offers customers a right of return for product that has been purchased from the Company. The Company estimates the amount of product returns and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company currently estimates product return liabilities based on analysis of historical data for the product or comparable products, as well as future expectations for such products and other judgments and analysis.

Chargebacks, Discounts and Rebates

Chargebacks, discounts and rebates represent the estimated obligations resulting from contractual commitments to sell products to its customers or end users at prices lower than the list prices charged to our wholesale customers. Customers charge the Company for the difference between the gross selling price they pay for the product and the ultimate contractual price agreed to between the Company and these end users. These reserves are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue and accounts receivable. Chargebacks, discounts and rebates are estimated at the time of sale to the customer.

Disaggregation of revenue

The Company’s source of revenue was from the sale of pharmaceutical products, which are equally affected by the same economic factors as it relates to the nature, amount, timing, and uncertainty of revenue and cash flows. For further detail about the Company’s revenues by product, see Note 19: Revenue by Product.

Contract Balances

The Company does not recognize revenue in advance of invoicing its customers and therefore has no related contract assets.

A receivable is recognized in the period the Company sells its products and when the Company’s right to consideration is unconditional.

There were no material deferred contract costs at September 30, 2020.

Transaction Price Allocated to the Remaining Performance Obligation

For product sales, the Company generally satisfied its performance obligations within the same period the product was delivered. Product sales recognized in the second quarter of 2020 from performance obligations satisfied (or partially satisfied) in previous periods were immaterial.

The Company has elected certain of the practical expedients from the disclosure requirement for remaining performance obligations for specific situations in which an entity need not estimate variable consideration to recognize revenue. Accordingly, the Company applies the practical expedient in ASC 606 to its stand-alone contracts and does not disclose information about variable consideration from remaining performance obligations for which the Company recognizes revenue.

Accounts Receivable

Accounts Receivable. Prior to the sale of the Hospital Products on June 30, 2020, accounts receivable are stated at amounts invoiced and certain other gross to net variable consideration deductions. An allowance for credit losses is established based on expected losses. Expected losses are estimated by reviewing individual accounts, considering aging, financial condition of the debtor, payment history, current and forecast economic conditions and other relevant factors. A majority of our accounts receivable are due from four significant customers. As of September 30, 2020, we have collected all of the accounts receivable outstanding as of June 30, 2020.

Newly Issued Accounting Pronouncements

Newly Issued Accounting Standards

Recent Accounting Guidance Not Yet Adopted

In December 2019, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, as part of its overall simplification initiative to reduce costs and complexity of applying accounting standards while maintaining or improving the usefulness of the information provided to users of financial statements. The FASB’s amendments primarily impact ASC 740, Income Taxes, and may impact both interim and annual reporting periods. ASU 2019-12 will be effective for fiscal years beginning after December 15, 2020, and interim periods within those fiscal years and early adoption is permitted. We are currently evaluating the impact of adopting ASU 2019-12.