XBRL 2.1 - HMRC - requires element

http://www.xbrl.org/Specification/XBRL-RECOMMENDATION-2003-12-31+Corrected-Errata-2008-07-02.htm#_5.2.6.1

There is an arc role in the HMRC taxonomy requiring elements to be reported.

Using the requires-element are role an instance of an concept as a fact requires another to be reported.

Tuple structures can enforce reporting however what about items not involved tuples.

This seems like an existence check


For example, the data that is normally into a paper form could be represented electronically using XBRL instances. To represent the “required field” idea, the taxonomy author can create a definitionArc with the http://www.xbrl.org/2003/arcrole/requires-element arc role value. This arc would link the concepts representing the required fields and an element representing the concept of the form itself.