“He said, ‘Look I don’t want to come back — I don’t think it’s the right thing for me to do,’” Mr. Moonves said in a telephone interview. “It was all handled with great care and great respect, and I was very sympathetic. You’re 45 years old, take care of yourself.”
The network said it was in discussions with Mr. Geller about a potential production deal with CBS Studios.
Mr. Geller declined to comment.
Mr. Geller’s medical leave occurred during the busiest stretch of the year for a network executive, a time when decisions are made on what pilots are picked up and the fall schedule is made final and presented to advertisers at the annual upfront presentations.
In a memo to the staff in March announcing his leave, Mr. Geller said: “The good news is the doctors have given me an excellent report card and say I’m on track for a full recovery. The bad news is that pilot season and the upfront isn’t the best environment to achieve that recovery. After consulting with my doctors, my husband and my family, I plan to take off a few more weeks and return at the end of May.”
During his medical leave, Mr. Geller did not have much contact with CBS executives and did not offer opinions on the final schedule that the network set.
Mr. Geller took over the job in September 2015 after CBS’s longtime entertainment head, Nina Tassler, retired. CBS finished this season as the most-viewed network for the 14th time in 15 years and gained some momentum from its new drama “Bull.”
But the network also fell to third place in the 18-to-49-year-old demographic, which is of paramount importance to advertisers. Graybeards like “The Big Bang Theory,” “NCIS” and “Survivor” continue to deliver strong ratings, but the network has been unable to find a new breakout hit for some time.
After Mr. Geller went on leave, Mr. Moonves thought it was possible that his president would not return, he said, and started considering contingency plans. He said he met with other TV executives “under very general circumstances.”
Ultimately, he looked within.
Mr. Kahl, 50, has long been CBS’s top scheduling executive and has worked with Mr. Moonves for more than two decades. Mr. Kahl took Mr. Geller’s place during CBS’s lively upfront presentation two weeks ago, which received warm reviews from ad buyers at Carnegie Hall. He joined CBS in 1996.
Mr. Moonves said Mr. Kahl got the job because of his “leadership ability.” He also said he was ready for the network to move on.
“It’s been a difficult time,” Mr. Moonves said. “People were concerned about Glenn and also concerned about what’s going to happen in the future. And now those questions are answered.”