How to show document type on AP check stub

Hello,

I am using the check on top/bottom graphical check layout.  I need to show the document type (INV, CRM, PMT) next to the document number on the check stub to help clarify for the vendor which lines are the applied payments or credit memos.  I have added the 'Document Type' field from every table in the report and none of them print any data. 

Any ideas?

Thanks ahead of time for any help.

Julie