All documents uploaded to R2 Docuo have an associated details window irrespective of whether or not they belong to a category.
To open a document's details window just select it from the results list and click the "Details" button on the button bar.
Other ways of opening the details window
You can also open the details window from the document's context menu by selecting "Details".
What the details window looks like
The details window consists of the button bar, main document, and the tabs General, Attachments and Activities.
The title of the window shows the document's category, code and name.