Delete Unused Paragraph Styles

Hi All,

I realize this one is probably pretty easy, but it has given me some grief these last few minutes. I'm trying to delete all unused paragraph styles in a document in InDesign CS. Here's the latest on what I have:

tell application "InDesign CS" to delete every unused paragraph style of document 1

I can't even get it to compile that. I've tried several variations, but all had the same result...it does not seem to like where I placed the word "unused", but I can't seem to figure out any other correct syntax.

Any help is greatly appreciated!