"I honestly feel the time has come that I have to get back to doing the other things that I do that I put on hold because I love Idol so much," Lopez told Ryan Seacrest on his radio show.
"I really have been torn. When I signed on to Idol, I signed on to do one year. I wound up doing two years because I fell in love with the show."
"I didn't know I would be so moved emotionally. It was just such a lovely surprise in my life to do it."
"You know, I have my movies and my music and my this and my that and it all kind of worked together for a while, but it gets more complicated as the kids get a little bigger. Something had to give. I really was dreading this phone call with you!"
"You're gonna make me cry," she continued. "The time has come."
Lopez has 4-year-old twins Emme and Max with now ex-husband Marc Anthony.
"It's one of those special things in your life that you just don't wanna walk away from. And that's why people are like, 'Oh, you're going back and forth.' But it's not that. It wasn't ever playing any games or doing anything, wanting more and more money. It was just being smart about making a business decision."
Her departure comes days after Steven Tyler also announced his exit from the FOX hit, which he described as his 'mistress'.