Talk about attempting to parse the language. Until they are printed, emails are NOT documents.
Donald Trump STOLE documents he had no right to take, out of the White House. These were physical documents, in file folders. Hillary Clinton stored emails which were sent to her via government email from co-workers, on her private server. Hillary didn't "take" anything. Everything on her server was sent to her email by others.
Your understanding of "copyright" law has nothing to do with who has the right to make photocopies. Written material is referred to as "copy". "Copyrights" say who owns the rights to profit from the written material.
If I write a book, I own the copyright to that book. No one can make a movie of my book, or use material in my book without my permission. If you want to turn my book into a play, I would want a payment for those rights, as the copyright owner.