The More Details toggle switch displayed the information about a document, comments on that document, revisions of that document and the Review Queue.
The Info tab states the information about the document that is selected including the Document Name, Folder is it is, File Type, Size, Date Uploaded and Last modified.
The Revisions tab displays all revisions to that document, along with the username of the person who revised it, and the date it was revised.
To access the comments section, the document must be assigned for review or approval.