Nick Cannon: Mariah Carey Will Be 'The Toughest Judge' On American Idol

Watch out Simon, Mimi is about to be unleashed!

According to Nick Cannon, his wife and new "American Idol" judge Mariah Carey will be the most fierce face to ever sit at the judges' table - but even tougher than Simon Cowell?

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"She's very serious about music and singing. She'll probably be the toughest judge that's ever been on [the] show," Nick told Access Hollywood backstage at Wednesday's "America's Got Talent."

In addition to her strong opinions, Mariah will also show off another not-often-seen side.

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"She's going to be amazing... people don't know my wife's sense of humor," Nick continued. "They're about to get the whole Mariah Carey, raw and uncut! And see the woman that I fell in love with."

But will she drop the diva behavior, for example showing up to work on time - as "Idol" is a live show for a majority of the season?

"Nah, that ain't happening," Nick joked. "It's Mariah Carey time!"

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"American Idol's" Season 12 returns to FOX in January.

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