"Friends and associates of the late Michael Neidorff, including former President Bill Clinton, paid tribute to him Sunday as a visionary business leader, loving husband and parent, and a philanthropist in his adopted hometown of St. Louis. About 600 people filled Graham Chapel at Washington University to honor Neidorff, the longtime CEO and chairman of Clayton-based Centene Corp. who died April 7 after a lengthy illness. He was 79. "We miss him beyond imagination and we treasure the memories,” said his son, Peter Neidorff, describing his father and mother, Noemi, as a “unit” during their 48 years of marriage.