"I'd go nuts, bored out of my mind. You have to evolve, you have to change. I like the challenge of launching something new."

With Cowell's deal with Fox expiring at the end of next season, that something new could be a U.S. version of his U.K. singing competition series "The X Factor." Any doubts about Cowell's role in the success of "Idol" disappeared when he launched "Factor" three years ago. The similarly formatted show became a massive hit that has since supplanted "American Idol" predecessor "Pop Idol."

The "Factor" success was worrisome enough for Fox to forbid Cowell from launching the show in the U.S. while he's under his current "Idol" deal. But all that could soon change. Between the continuing popularity of "Idol" and Cowell's ownership of "Factor," he's armed with both a carrot and a stick.

Asked if he would want to stay on "Idol" if the series ever slips from No. 1 in the ratings, Cowell burst out laughing at the apparent obviousness of the answer.

"Absolutely not!" he said, looking horrified. "Being No. 1 is verging on an obsession with me. I don't like being No. 2. I don't mind when you start at No. 10 -- people don't always go on as No. 1 -- and you've got somewhere to go. But if you're at the point you've reached it, of course you want to stay there."

Though the "Idol" audience has declined over the past few seasons, the show remains far and away the ratings champ, with about 22 million viewers per episode. No other program approaches its popularity.

Unlike many in the TV business, Cowell rejects the claim that "Idol" ratings erosion is inevitable.