Eric, Is this happening in all the documents or just one particular doc??
If its one particular document then I would suggest that you try steps in : http://helpx.adobe.com/indesign/kb/troubleshoot-damaged-indesign-documents.html
If its all the documents then delete the preferences, refer the document for locations : http://helpx.adobe.com/indesign/kb/indesign-preferences-support-file-locations.html
Also It would be helpful if you let us know if the issue is with one particular language or all the languages ( If you have multiple language text )
Every month we create a new document and it seems to happen just about every month.
The language is all English.
Try the first step post you get the error (Saving as IDML would be my best bet post you get the error ) also you might want to install the language files again, steps can be found as specified in the following doucment : Add or remove Hunspell dictionaries | CC, CS6