I would say you need both, the process of creating the document and the document itself are two different entities. I'd also add that the line from process to document could be of a different type, maybe dashed, just to show that it is not part of the flow sequence, but a consequence of that sequence.
If you are using Viso 2010 then you could use a container , I don't think grouping woule be appropriate here. Add the process and the document to the container.