I Want to Write a Novel

I actually want to write an entire series of novels. An epic saga. I am setting it in future and having different types of sci-fi technology as well as fantasy elements. I am also going to include political issues in it as well as metaphors and parables for race, culture, religion, philosophy and the meaning of life. I am naming some of my characters after famous figures from history. I already have a basic idea for the plot of the entire series. The main thing I am struggling with is creating the setting, making it detailed and realistic and specific plot events and dialog. I am trying to do research for the book so that I will know what I am talking about and can describe and imagine how things would turn out realistically in the novel. I want to know what I am talking about and not seem like an amateur writing about stuff I know nothing about. The problem is that I spend all my time thinking up ideas for the novel and very little time actually writing.