For one reason or another, my Word suddenly decided to stay always on top of all other windows. This is terribly annoying. The odd thing is: of three documents I have open, two are on top of everything else, and one behaves normal.

I found one other mention of this behavior. I wonder whether this is a known bug and whether there's a workaround. Sometimes closing all windows helps, but later the behavior creeps back. Other Office products don't seem to show this behavior.

I'm using Microsoft Office Professional Plus 2010, 14.0.4760.1000 (64 bit).