This detail group contains some elements which display in the background and some which display in the foreground. Detail groups must be able to be displayed as a unit in either the foreground or background, so this type of mixture is not allowed. 
   Namespace:   Autodesk.Revit.DB  
  Assembly:   RevitAPI  (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
Syntax
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