Detached views are
   views that are shown in a separate window with a smaller trim. They work like other views
   except they are always shown in front of the Workbench window. 

You can create a new detached view by dragging any open view outside of the Workbench window or by selecting Detached from the menu that opens when you right-click the view's tab.

Detaching views
Moving and docking views
Maximizing a view or editor