Currently, the Description field is always at the bottom of the Ideas form when the entered record is viewed within the system. Most users want to see the Description immediately after the Name/Title when viewing the entered record in the system. Please consider making this data field one that may be rearranged, the order on the system layout may be changed. (It may already be changed on the portal form - this would allow the portal form layout and the record system layout to match.)
The idea description field now appears at the top of the page by default or you can move it to its own tab. You can also customize the new idea form to place the description field anywhere you like.