The 69-year-old Schieffer, who turns over anchoring duties to Couric Tuesday, said his 18 months on the show have been thoroughly enjoyable.
"I'm the luckiest guy in the world that I got a chance to do, as an adult, what I wanted to do as a young person." said Schieffer. "I've had a wonderful, wonderful life, and it's a longer life than I probably deserved and frankly, that even I thought I would have."
Before taking over for former host Dan Rather last March when Rather left the broadcast amidst the National Guard document scandal, Schieffer had also worked at the Pentagon, Congress and the U.S. State Department, making him one of the few journalists to have worked all four major Washington assignments.
CBS said that Schieffer credits his career success, his happiness in life, and his ability to cope after being diagnosed with bladder cancer three years ago to his wife, his daughters, and his mother.
Notable deaths of 2014 [PHOTOS]