Pretty much, yes. Amusingly, language is "fuzzy" by nature, which is why human-human communication is so verbose. So the word "ideas" has debatable meaning. What you call an idea, I may call a whole business plan, or vice verse, or some other combination of things.

Aside of that, someone indeed has created a "business plan" market website. I don't remember what it's called, but if you can't find it, I can try fishing it out.