diff --git a/Code/Mantid/docs/source/concepts/InstrumentDefinitionFile.rst b/Code/Mantid/docs/source/concepts/InstrumentDefinitionFile.rst
index fb052627801bded2ddbe86713100fdb29b095fc6..7ab7e415c3cf14c3aa94bddcfe7354e3824a7015 100644
--- a/Code/Mantid/docs/source/concepts/InstrumentDefinitionFile.rst
+++ b/Code/Mantid/docs/source/concepts/InstrumentDefinitionFile.rst
@@ -1345,8 +1345,7 @@ Deprecated Features
 
 The following features are now deprecated and should no longer be used.
 
-mark-as="monitor"
-#################
+*mark-as="monitor"*
 
 The following notation to mark a detector as a
 monitor is now deprecated: