The ink has barely dried on Mariah Carey's American Idol contract, but the new judge isn't shy about telling the producers exactly what she requires... starting with an $18 million a year salary!

"Mariah was adamant about getting more money than J.Lo, whose $12 million seat she's about to fill," says an insider.

Besides the moolah, the 43-year-old pop diva is dead set on looking better than her predecessor too. "J.Lo showed up week after week in some pretty amazing outfits, and Mariah wants to make sure that hers are better," the source reveals.