The US SEC made available a web page called "Public Validation Criteria". The web page is located here and states:
"These validation criteria reflect SEC staff’s current views on appropriate validation criteria for XBRL tagging to improve the consistency and quality of XBRL documents submitted to the SEC. We are publishing this list to help filers and data tagging software companies improve existing products or create new products to automate testing for these criteria. They do not reflect an existing SEC requirement and may change in the future."
This is great addition to guidance which is needed to create the needed "consistency and quality of XBRL documents" as stated by the SEC. I would speculate that there will be more rules such as these created as inconsistencies and other problems related to data quality are discovered. It is great that the SEC is doing this proactively.