Kara DioGuardi. LOS ANGELES, Sept 3 (Reuters Life!) - Songwriter Kara DioGuardi has quit American Idol, the third of four judges to leave the top-rated U.S. television singing contest this year following Simon Cowell and Ellen DeGeneres.

Kara DioGuardi. LOS ANGELES, Sept 3 (Reuters Life!) - Songwriter Kara DioGuardi has quit American Idol, the third of four judges to leave the top-rated U.S. television singing contest this year following Simon Cowell and Ellen DeGeneres.

Songwriter, singer and former American Idol judge Kara DioGuardi has listed a home in Studio City at $10 million.

Songwriter, singer and former American Idol judge Kara DioGuardi has listed a home in Studio City at $10 million.

Former American Idol judge Kara DioGuardi, who recently made her Broadway debut as Roxie Hart in Chicago , will return to her roots when she judges the Cell Block Idol contest, where the winner will not only be named the “Cell Block Idol,” but will also score tickets to Chicago and a meet-and-greet with DioGuardi.