Multiple drop down windows that auto-close when opening another

Multiple drop down windows that auto-close when opening another

I have an example of what I'm working on here at JSFiddle
http://jsfiddle.net/OfSilence/zFuUp/. I'm trying to find a way to make the
drop-down that's opened auto close when opening another. All the solutions
I find either keep anything from opening or opening & closing everything
at the same time. Keep in mind on the final page their will be around 30
of these drop-downs. Any help would be greatly appreciated! JSFiddle