Apart form the mis-spelling of float
I assume you meant to float the 'sidebar' rather than the 'navbar' (as indicated in your post). Although you could also float the navbar within
the sidebar if you want.
Once you've added float to the sidebar you will also need to add another 'div' after your main div with the css property 'clear: both;' - otherwise the wrapper div will collapse and have no height.
Or, if you prefer, you could give your wrapper a height.