This article references the most recent Documents .pdf

Database (Portal Docs):

Database Folders are folders that are created in the OnSemble database where you can upload documents directly to the portal. Database documents allow you to set up reader and writer permissions, see document versions, and subscribe to changes.

Root Level - Writing/Editing and Reading/Viewing: Controlled by visiting Portal Tools -> Manage Portal Documents -> Manage Folders. Select Edit next to the folder you need to change permission for.

Sub Folder Level - Writing/Editing and Reading/Viewing: Controlled by visiting your Portal Document Repository. Portal Documents (ie: https://YOURPORTALNAME.com/Documents/DocumentExplorer.aspx) and choosing Properties from the drop down next to the sub folder name. 

F.A.Q.

Question: Why is the Document not showing in my List Island in a workgroup?

Answer: Workgroups need to have permission to read/view, just the same as users do. If the Workgroup can't "see" the documents, then it can't display the document.

Question: How are Permissions initially determined?

Answer: Folders inherit from the folder "above." You can remove permission on a sub folder, and it will remove from the sub folders below that.