Nigel Lythgoe, Jimmy Iovine Nigel Lythgoe, Jimmy Iovine

Major changes to American Idol are firming up, among them deals for Nigel Lythgoe to return as executive producer and music executive Jimmy Iovine to play an on- and off-camera role.

Lythgoe, who left Idol two years ago, has signed his deal to return to the show, Fox announced Thursday. The So You Think You Can Dance judge and executive producer will run the show alongside longtime executive producer Ken Warwick. Lythgoe will not, however, judge Idol, he tweeted.

"American Idol became a juggernaut of epic proportions, but to me it was always like home," Lythgoe said in a statement. "I am elated and honored to be rejoining childhood friend and fellow executive producer Ken Warwick, and look forward to creating more magic."

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One change Lythgoe says he would like to see? The return of Paula Abdul. That might be difficult, as Abdul has landed a dancing competition show on CBS.

"I still love Paula," he told Variety. "She's signed to CBS, probably exclusively, but I'd recommend we have her in a heartbeat."

Lythgoe also addressed the reports that Jennifer Lopez and Steven Tyler are in talks to join the show's judging panel.

"They can knock [Lopez's] film career, but [audiences] know she's a good actress," Lythgoe said. "And as J. Lo, she had some great pop records. If she joins, I'm happy."

As for Tyler, Lythgoe says the Aerosmith frontman's unpredictability makes him a good candidate.

"He has come through that whole rock 'n' roll circus," Lythgoe said. "Why wouldn't you want a legend there? You never know what he's going to say. That, as a TV producer, you're interested in."

News first broke last week that Lythgoe was negotiating to go back to the show, which he helped start in the U.S. before leaving after Season 7.

Iovine, chairman of Universal Music Group's Interscope Geffen A&M record label, will serve as "a mentor of sorts" on the show, according to the Los Angeles Times. As a record producer, he has worked with such artists as Bruce Springsteen, U2 and Eminem.

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News of Iovine's joining the show comes one day after The Wall Street Journal reported that Idol had struck a new deal with Iovine's Interscope Geffen A&M, which replaces Sony Music as the distributor and promoter of music by the contestants and winners.

Sony will stick with former Idol judge Simon Cowell, who in January announced a long-term all-encompassing partnership with the label. Their first project? Cowell's upcoming music show The X Factor.

No word on what kind of screen time Iovine will get on Idol, but it could be in keeping with the limited appearances by Sony Music Entertainment chief creative officer Clive Davis, who appeared on the show several times as a guest judge.  

Fox declined to comment on Iovine.

(Additional reporting by Denise Martin)