Is it possible to change the way that docked tool windows in IDEA are laid out?
Currently, the bottom most window takes all the horizontal space, and the left and right
This feature is available since IntelliJ IDEA 13 release.
Settings (Preferences on Mac) | Appearance & Behavior | Appearance | Widescreen tool window layout.
Settings
Preferences
Appearance & Behavior
Appearance
Obsolete original answer:
No, such configuration is not supported at the moment, feel free to submit a feature request.