If you are talking about the translation results window, it's not removable but you have the option of having it display on top or on the right side using F11.
If you do concordance search (Ctrl+K), the search results window pops up and you can move it to your second monitor.
Are floating windows for the TM. glossary, concordance etc. possible at all? I have looked everywhere but cannot find any such option. I have two large monitors and I would like to have the editor window on one screen and all additional windows at the other one.