The message “formula:assertionunsatisfied” can be both an error and a warning, which means that it can be both a blocking and a non-blocking issue.
What Is the Issue?
“Formula:assertionunsatisfied” is the error id of validation errors related to the taxonomy itself. The validation rules within the taxonomy are referred to as “assertions” and a list of them can be found in technical XBRL documents.
Fixing the Issue
Most often issues which give the message “formula:assertionunsatisfied” are simply warnings, which mean you do not have to solve them immediately. If they need to be solved, you can do so by referring to the specific error explanation.
The two most common issues related to this error message is a missing element or an element which should be positive instead of negative. In the both cases correcting the information will most likely fix the issue.