In addition, Jimmy Iovine, chairman of Interscope Geffen A&M Records and co-founder of Beats Audio, will be the show's in-house mentor to the competing singers. The announcement was made Wednesday morning from the stage of The Forum in Los Angeles by Ryan Seacrest, the show's host.
For Lopez, the deal also includes a "first-look" theatrical movie agreement with Fox Filmed Entertainment.
While rumors of Lopez joining the show as a judge have been in the works for weeks, one major negotiating hurdle was a Lopez film deal with her company, Nuyorican Productions. The belief was that Fox wasn't jazzed about adding such a clause, given the lukewarm performances of her recent movies.
She and Tyler start up as judges for the show's 10th season, which begins in January. Randy Jackson, who has been with the show since the beginning, will continue as the third judge.
Returning producer Nigel Lythgoe believes a return to the three -judge setup would allow for more emphasis to be placed on the singing talent.
Peter Rice, chairman of entertainment for Fox Networks Group, stated: "Jennifer and Steven have made the journey from aspiring unknowns to global superstars, which makes both of them uniquely qualified to help discover the next 'American Idol.'"
In commenting about Lopez and her overall Fox deal, Jim Gianopulos and Tom Rothman, chairmen/CEOs of Fox Filmed Entertainment, said: "Jennifer is a true entertainment powerhouse who has made a tremendous impact on pop culture."