Cornelius, the fourth child of Harry and Verlean Tidwell, was born in Independence, Kansas. After graduating from Independence High School, he attended Independence Community College where he served as Class Treasurer from 1965-1967 and as the first President of the Theatre Players. After service in the U.S. Army, where he was stationed in Germany at the height of the Viet Nam War, he moved to Omaha, Nebraska. There he earned a business degree at Belleview College and married Elaine. They have two children: Stephen and Matthew.