Way to jump to Javadoc for any class?

I'm interested if there's a way to get Idea to display (in a popup or a browser) the Javadoc for any class/method/property/etc. for any class imported or referenced in your project.    I read this thread: 

http://devnet.jetbrains.net/message/5223645#5223645

but that only seems to work for internal classes in the same project, or module.   I came across this problem because I was trying to look up the Javadoc for a Junit class and (of course) Ctrl-Q told me that the Javadoc was not found for org.junit.Assert.

Of course if you know the FQ class you can google it and (eventually) find what you're looking for, but it would be nice to be able to jump directly to what you need.