Simple Extrude/Scale question

I am modeling a tall building and I want to create a ledge. I selected all the top edges, hit extruded/esc and then scaled them out. Most edges did what I wanted them to, however, the edges in the circled areas didn’t scale out as I expected them to. I’m sure this is a simple procedure, but I have not been able to find any info that addresses this.

I’ve wasted a few hours on this, so any help would be appreciated!

WOW. That’s just what I need! Thanks so much!

One quick question: I downloaded the .zip file and installed it. When I exercise the extrude option, I don’t get any options, such as width. Do I have an older version?

Options are in the toolshelf or by pressing F6

Found it. Thank you. I appreciate your time!