Darnell, who has been with Fox for 18 years, was offered a new long-term contract, but said he didn't accept it because he wanted to try his hand at other options, The Hollywood Reporter said Friday.
"I'm extremely grateful that Fox has offered me a new long-term contract (and anyone who knows me won't believe I'm saying this), but I've decided it's time for a change. With my current deal ending in June, and having been here for 18 years (kind of a record in Hollywood), I had to make a decision: either stay (and basically admit to myself I was going to retire at Fox ... not a terrible choice) or leave and try something new. I've been in 'Reality' since before it was even called that, and it has truly been an amazing ride," Darnell said in a statement released Friday.
He oversaw the creation of "Idol" -- television's No. 1 series for nine consecutive seasons, which has recently posted disappointing ratings -- as well as "The X Factor," "So You Think You Can Dance," "MasterChef," "Hell's Kitchen" and "Kitchen Nightmares," The Hollywood Reporter said.
"Mike took risks at a critical time and was a pioneering force in shaping the reality programming genre that exists today," said News Corp. Chairman and Chief Executive Officer Rupert Murdoch. "He's a smart and fearless executive who will be missed."
Notable deaths of 2014 [PHOTOS]