Related Party Transactions	12 Months Ended
Related Party Transactions	Sep. 30, 2020
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions Management Agreement Upon completion of the Merger, the Company and Holdings entered into the Management Agreement, dated as of the Merger Closing Date, pursuant to which Access provided the Company and its subsidiaries with financial, investment banking, management, advisory and other services. Pursuant to the Management Agreement, the Company paid to Access an annual fee on quarterly basis and reimbursed Access for certain expenses incurred performing services under the agreement. The Company and Holdings agreed to indemnify Access and certain of its affiliates against all liabilities arising out of performance of the Management Agreement. As a result of the completion of the IPO, the Management Agreement terminated in accordance with its terms and the Company paid to Access a one-time termination fee and a fee for transaction services in an aggregate amount of $60 million. The Company recorded these fees within selling, general and administrative expenses in the consolidated statements of operations for the fiscal year ended September 30, 2020. Prior to the termination of the Management Agreement, the Company incurred costs associated with the Management Agreement of approximately $7 million, $11 million and $16 million for the fiscal years ended September 30, 2020, September 30, 2019 and September 30, 2018, respectively. Such amounts have been included as a component of selling, general and administrative expense in the accompanying consolidated statements of operations. Lease Arrangements with Related Parties On March 29, 2019, an affiliate of Access acquired the Ford Factory Building, located on 777 S. Santa Fe Avenue in Los Angeles, California from an unaffiliated third party. The building is the Company’s new Los Angeles, California headquarters and as such, the Company is the sole tenant of the building acquired by Access. The existing lease agreement was assumed by Access upon purchase of the building and was not modified as a result of the purchase. Rental payments by the Company under the existing lease total approximately $13 million per year, subject to annual fixed increases. The remaining lease term is approximately 10 years, after which the Company may exercise a single option to extend the term of the lease for 10 years thereafter. On August 13, 2015, a subsidiary of the Company, Warner Music Inc., entered into a license agreement with Access for the use of office space in the Company’s corporate headquarters at 1633 Broadway, New York, New York. The license fee of $2,775 per month, plus an IT support fee of $1,000 per month, was based on the per foot lease costs to the Company of its headquarters space, which represented market terms. For the fiscal year ended September 30, 2020, an immaterial amount was recorded as rental income. The space is occupied by The Blavatnik Archive, which is dedicated to the discovery and preservation of historically distinctive and visually compelling artifacts, images and stories that contribute to the study of 20th century Jewish, WWI and WWII history. On July 29, 2014, AI Wrights Holdings Limited, an affiliate of Access, entered into a lease and related agreements with Warner Chappell Music Limited and WMG Acquisition (UK) Limited, subsidiaries of the Company, for the lease of 27 Wrights Lane, Kensington, London. The Company had been the tenant of the building which Access acquired. Subsequent to the change in ownership, the parties entered into the lease and related agreements pursuant to which, on January 1, 2015, the rent was increased to £3,460,250 per year and the term was extended for an additional five years from December 24, 2020 to December 24, 2025, with a market rate rent review beginning December 25, 2020. License Agreements with Deezer Access owns a controlling equity interest in Deezer S.A., which was formerly known as Odyssey Music Group (“Odyssey”), a French company that controls and operates a music streaming service, formerly through Odyssey’s subsidiary, Blogmusik SAS (“Blogmusik”), under the name Deezer (“Deezer”), and is represented on Deezer S.A.’s Board of Directors. Subsidiaries of the Company have been a party to license arrangements with Deezer since 2008, which provide for the use of the Company’s sound recordings on Deezer’s ad-supported and subscription streaming services worldwide (excluding Japan) in exchange for fees paid by Deezer. The Company has also authorized Deezer to include the Company’s sound recordings in Deezer’s streaming services where such services are offered as a bundle with third-party services or products (e.g., telco services or hardware products), for which Deezer is also required to make payments to the Company. Deezer paid to the Company an aggregate amount of approximately $42 million, $49 million and $39 million in connection with the foregoing arrangements during the fiscal years ended September 30, 2020, 2019 and 2018, respectively. In addition, in connection with these arrangements, (i) the Company was issued, and currently holds, warrants to purchase shares of Deezer S.A. and (ii) the Company purchased a small number of shares of Deezer S.A., which collectively represent a small minority interest in Deezer S.A. The Company also has various publishing agreements with Deezer. Warner Chappell has licenses with Deezer for use of repertoire on the service in Europe, which the Company refers to as a PEDL license (referencing the Company’s Pan European Digital Licensing initiative), and for territories in Latin America. For the PEDL and Latin American licenses for the fiscal years ended September 30, 2020 and 2019, Deezer paid the Company an additional approximately $2 million and $1 million, respectively. Deezer also licenses other publishing rights controlled by Warner Chappell through statutory licenses or through various collecting societies. License Agreements with Snap In 2020, a subsidiary of the Company entered into a worldwide (excluding China) recorded music license agreement for a 24-month term and Warner Chappell also entered into a 2-year license with Snap, Inc. covering the personal, non-commercial use of up to 60 second song clips from WMG’s catalog in messages across Snap properties. The Company earned approximately $500,000 in connection with the foregoing deals during the fiscal year ended September 30, 2020. The Company’s Chairman, Michael Lynton, is also a director of Snap, Inc. Distribution Agreement with Mattel In 2020, a subsidiary of the Company entered into a 3-year digital distribution and physical license of the existing catalog plus new material of Mattel Inc. The Company earned approximately $200,000 in connection with the foregoing arrangements during the fiscal year ended September 30, 2020. The Company’s director, Ynon Kreiz, is also the CEO of Mattel Inc. Investment in Tencent Music Entertainment Group On October 1, 2018, WMG China LLC (“WMG China”), an affiliate of the Company, entered into a share subscription agreement with Tencent Music Entertainment Group pursuant to which WMG China agreed to purchase 37,162,288 ordinary shares of Tencent Music Entertainment Group for $100 million. WMG China is 80% owned by AI New Holdings 5 LLC, an affiliate of Access, and 20% owned by the Company. On October 3, 2018, WMG China acquired the shares pursuant to the share subscription agreement.