Det received his B.A. in English Literature from San Francisco State University in 1965. He joined the Peace Corps in 1967 and served in Nepal as an agriculture extension volunteer in the eastern Tarai. After Peace Corps, he returned to San Francisco State to complete an M.A. in Humanities and English Literature in 1972. From 1970 to 1986, he worked for the Forest Service as a writer-editor, biological technician, and forest pathologist in the Pacific Southwest Regional office in San Francisco. He received his M.S. in Plant Pathology at the University of California, Berkeley in 1979 and his Ph.D., also in Plant Pathology, in 1991. Det was a postdoctoral fellow in the Bruns lab until March of 1996, where he studied the evolution and systematics of the stem rust fungi, Cronartium and Peridermium spp., which infect pines throughout the northern hemisphere. From March 1996 through January 1998, Det worked in the Conservation Genetics Laboratory at San Francisco State University, coordinating an NSF-sponsored Undergraduate Faculty Enhancement course in Molecular Genetic Analysis. He is currently employed at the Institute of Forest Genetics, USDA Forest Service, PSW Research Station in Placerville, California.