A show insider told UsMagazine.com: Mariah is getting paid $18 million with a one-year option to do 'Idol', making her the highest paid judge on any music competition show."
The singer's predecessor on the show, Jennifer Lopez, earned around $12 million dollars per season, Christina Aguilera negotiated a reported $10 million for the third season of 'The Voice', while Britney Spears will make approximately $16 million for her stint on 'The X Factor' USA.
Five-time Grammy Award winner, Mariah, confirmed on Monday that she had agreed on a deal with the television talent show.
She said: "As a singer, songwriter and producer, it's going to be fun and rewarding to help find new talent and give back to American Idol.
"I'm currently in the studio working on my new album and its first single, 'Triumphant,' which will be out early next month. I can't wait to channel my creative energy as a part of this show which is a massive global phenomenon."