Abdul recently admitted that she is considering "moving on" from the network's talent competition to pursue other projects.
Meanwhile, Cowell has hinted that next year's ninth season could be his last - especially if ratings for the programme continue to drop.
Idol is currently averaging 26.3m viewers per episode, which is a fall of 8% from last year's figures.
However, speaking to Reuters, Fox's president of alternative programming Mike Darnell insisted: "Idol at the moment is the most dominant it has ever been."
On Abdul and Cowell's future, he added: "It is our hope and my personal wish that both of them stay for as long as the show is on."
Lil Rounds and Anoop Desai were both eliminated from the reality series earlier this week.