The news Friday comes a day after the Aerosmith frontman also announced his exit. It leaves Randy Jackson as the only remaining "Idol" judge, though speculation has run rampant that he might exit after being the only panelist to stick with the show for each of its eleven seasons.
If Jackson does leave, the show will begin its 12th season next year with a brand-new judging panel for the first time since its debut.
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Lopez announced her exit in an interview Friday with Ryan Seacrest during his radio show, "On the Air."
"Something has to give, and that's, I think, where I am right now," she said.
When Seacrest pressed her on whether the two are still "co-workers," she said, "I honestly feel like the time has come that I have to get back to doing the other the things that I have to do, that I've put kind of on hold because I love 'Idol' so much."
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"We had an amazing run," she added.
She remained open to returning for the first episode of the show's next season. But she said her children and career goals didn't leave her time to return full time.
The news means "Idol" is once again in flux after losing its ranking as TV's No. 1 show last season, after eight years at the top. NBC's "Sunday Night Football" beat "Idol" in the ratings last season, and "Idol" found itself in a tight race for second place with NBC's upstart singing show "The Voice."
Tyler and Lopez came aboard as judges for the show's 10th season to replace departing judges Simon Cowell — who left to launch the American version of singing competition "The X Factor" — as well as Ellen DeGeneres and Kara DioGuardi. Original judge Paula Abdul was the first to exit the show.