Since IDEA 16 EAP, there’s an action for that. It’s in the menu:
Code | Move Element Left/Right
Keyboard shortcuts are Alt+Ctrl+Shift+Left/Right (Alt+Cmd+Shift+Left/Right for OSX).
See http://blog.jetbrains.com/idea/2016/01/intellij-idea-16-eap-improves-editor-and-vcs-integration/ for more details.