"I felt like I won the lottery when I joined American Idol two years ago, but I feel like now is the best time to leave Idol," DioGuardi said in a Fox press release released late Friday evening on the eve of the Labor Day holiday weekend.
"I am very proud to have been associated with American Idol -- it has truly been an amazing experience. I am grateful to FOX, [Idol's] FremantleMedia and 19 Entertainment [production companies], as well as the cast, crew and contestants, for all they have given to me. I look forward to my next challenge, and want to thank everyone who has supported me. All the best to everyone on Season 10!"
Fox's statement did not elaborate on why DioGuardi is leaving. Instead, network executives andAmerican Idolproducers thanked DioGuardi for her contributions over the last two seasons.
"Kara was a great addition to our Idol family," Fox reality chief Mike Darnell said. "She will be missed, and we wish her continued success."
"Kara is one of the world's best songwriters," American Idol creator and producer Simon Fuller said. "I will miss having her on the show, but I look forward to working with her in music for many years to come."
"We are very grateful for the time she spent on the show, and we wish her nothing but the best in all her future endeavors," American Idol producer Cecile Frot-Coutaz added.
DioGuardi's American Idol departure had been anticipated since late July when widespread reports that the show had fired DioGuardi and settled on a new three-person judging panel consisting of Aerosmith singer Steven Tyler, singer and actress Jennifer Lopez and returning judge Randy Jackson surfaced.
Lythgoe had been an outspoken critic of American Idol's decision to add DioGuardi and expand the judging panel to four judges after his 2008 departure. In addition, he had also repeatedly told reporters he would address Cowell's exit by replacing Idol's entire judging panel and returning to a three-judge format if he were still in charge of the show.
Fox subsequently confirmed Lythgoe's return but has declined comment on the reported judging changes, saying only that it expects Idol's tenth-season judging panel to be in place and announced by the time the season's nationwide callback auditions with the judges begin in mid-September.
Early last month, DioGuardi's father Joe DioGuardi, a Republican U.S. Senate candidate in New York, said DioGuardi learned of her reported American Idol axing from media reports and had yet to hear anything from Fox or the show's producers.
"Would you believe that she did not hear, and still has not heard, anything?" he told New York's Capital Tonight political TV program. "She read it the way that you did and I did. In fact, her disappointment is that that is the way that she is being treated and feels that is not proper."
"Does she want to do it another year? I think so, but she just got married and she wants to have a family. So maybe this is a good opening for her too," he added. "She has plenty of options... and I think she will at some point confront them on that."
However late last month, E! News suddenly reported that DioGuardi had actually tried to quit American Idol two months ago but Fox had yet to respond to her request, citing an unnamed source.