At first, Green Day was part of the punk rock culture at 924 Gilman Street in Berkeley, California. Its album "Dookie" (1994) became a success. Soon, it sold more than ten million copies in the United States alone, and 20 million copies worldwide. The album was well reviewed and the band were praised for its music and sales. Green Day had three more albums after that, "Insomniac", "Nimrod" and "Warning". They were still successful albums, reaching double platinum, double platinum, and gold status respectively. However none of these albums sold as well as their third album, "Dookie". Green Day's 2004 rock opera "American Idiot" sold six million copies in the United States.