I suggest you reset your cache and preferences. Troubleshooting 101: Replace, or "trash" your InDesign preferences
I see you are working on a custom workspace named "Phillip", so if you want you can first save it on some other location and then clean your cache and preferences.
To save the workspace:
1. Go to: ~/Library/Preferences/Adobe/Adobe InDesign
2. Navigate to Version X.0/en_us/Workspaces and you'll find your workspace files
Copy and place the workspace files in some other location (say Desktop). Clean cache and preferences and then place your workspace back at the same location.
Or you can first rename your cache and preference folders, and then see if that helps.
I recommend that after you've reset preferences and have redone all of your settings as you like them that (after quitting the program) you make a copy of this new "pristine" version of your preference file and save it for future use. It is a big time saver to be able to trash preferences and replace them with a version that is already as you like them.
Thank you for your fast and useful answer! I'll try that :-)
Special Thanks to you, Bill :-) That will make it a lot easier in the future!