diff --git a/app/models/attachment.rb b/app/models/attachment.rb
index bbc9a4660..7bc49472e 100644
--- a/app/models/attachment.rb
+++ b/app/models/attachment.rb
@@ -66,6 +66,7 @@ class Attachment < ActiveRecord::Base
     :scope =>
       proc do
         select("#{Attachment.table_name}.*").
+          where(container_type: 'Document').
           joins(
             "LEFT JOIN #{Document.table_name} " \
             "ON #{Attachment.table_name}.container_type='Document' " \