BEVERLY HILLS, Calif. — Mariah Carey will be joining the cast of “American Idol.”

She told a meeting of the Television Critics Association that she is excited to join as a judge and it all happened quickly.

Executive producer Nigel Lythgoe earlier added uncertainty to the question of who will judge next season, saying there’s a slender possibility that Jennifer Lopez might return. His reasoning: Since she told “Idol” host Ryan Seacrest she was 99 percent sure she was leaving, that means there’s a 1 percent chance she won’t, Lythgoe said Monday.