American Idolis ending after 15 seasons next year, but Fox executives promise the final run will be a season-long celebration.

"It was not an easy decision," Fox COO Joe Earley told reporters Monday morning. "American Idol has been such a vital part of Fox for its run and we spent a lot of time talking with producers about the future of American Idol. Collectively, we all arrived at the conclusion that it was time to bring the show to an end, but a way that felt special and celebratory and treated the show the way it deserved to be treated. So ... it is going to be a true season-long celebration. We're already talking about surprises we can have for the fans to make it feel special and send it off in a way that's as significant as the run it's had on our network."

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Jennifer Lopez, Harry Connick Jr., Keith Urban and Ryan Seacrest are all returning for the show's last season, but there's a good chance viewers will get to see some familiar faces. Asked about the possible return of original judges Simon Cowell, Paula Abdul and Randy Jackson, Fox TV Group Co-Chairman Dana Walden said, "We would welcome any of them back. ... Having spent a lot of time with former Idol judges, there is enthusiasm about coming back and paying tribute to a show that launched many, many successful careers. I think there is going to be a lot of enthusiasm around former contestants and judges being a part of the show."

But what about Season 1 co-host Brian Dunkleman? Walden laughed, "That is a really good question. Where is Brian Dunkleman? If you get me his number, I will call and invite him."

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Another big question about the new schedule was New Girl being delayed until January, when it will return for a a full 22-episode season. The move is a part of an overall strategy by the network to cut out reruns and lengthy breaks for all of its shows, Fox TV Group Co-Chairman Gary Newman said. "Contemporary viewers have a lot of choices and the erratic scheduling ... of the past just [doesn't] work anymore. Many of our shows this season will have two [runs] with two virtually uninterrupted runs of originals: Part 1 in the fall leading a big cliff-hanger and then Part 2 in the spring. This will give more consistency for our viewers."

Other notable news included:

- Fox will not air Empire reruns over the summer, but Walden said, "We just signed Ne-Yo, who is going to write original music for the second season along with Timbaland." Season 2 will consist of 18 episodes, up from Season 1's 12, and will be split into two halves.

- Another version of 24 is in development, but it's too fairly early for execs to say anything more.

- The X-Files, which goes into production in June and will premiere in January, will be "a very huge reward for fans of the show," Walden said.

Watch the Idol judges share their weirdest talents and more: