Isn't there some shortcut that takes you to context specific help? For example, if I have my cursor on System.out.println, isn't there some shortcut key I press that takes me to the documentation on this particular method or class where the method is declared?
View documentation ("Quick Documentation" action): Ctrl+Q
View external documentation ("External Documentation" action):
Shift+F1
For this to work you need to configure your project so that IntelliJ knows where to look for it (see here).