Idelson started out as a child actor, working in film, television and
radio. When he became an adult, he left show business for a time and
worked in real estate. He missed it, so he managed to break into show
business again with the help of his friend
Richard Matheson by writing the "Long
Distance Call" episode of
The Twilight Zone (1959) with
Charles Beaumont. From there he worked as
a TV writer, producer and occasional actor. His most popular role as a
performer was probably Herman Glimscher, Sally's bumbling boyfriend on
The Dick Van Dyke Show (1961).