CommonDocuments folder in iCloud storage

On my iPad, under Settings > iCloud > Storage > Manage Storage I see a folder called CommonDocuments. It has a blank grey icon. It contains a couple of files (a pdf and a jpg) that I copied to the iCloud using an app (Documents) on my iPad. The documents can't be opened or viewed when I am in the CommonDocuments folder, though they can be deleted (swipe).

My question: how can I access these documents on my iMac via iCloud? There's no folder called CommonDocuments, but obviously these docs are there somewhere in my iCloud.