How to enforce content in XBRL instance document

[Kamal Karunaratna]

We have XBRL 2.1 definition taxonomy with large number of items. We are creating number of reporting taxonomies using the definition taxonomy for data collection. We would like to enforce that the instance documents created from a specific reporting taxonomy only contain items included in that reporting taxonomy only. We do not want any other item defined in the definition taxonomy to appear in instance documents.

Has anybody implemented any method to enforce these requirements?

[XMeister]

You may want to review the methodology used by the SBR effort in the Netherlands - see http://www.xbrl-ntp.nl/english - which had an architecture with a single taxonomy brought into different forms. You could use the Formula linkbase. You could use the requires-element definition linkrole within each reporting taxonomy.

[Ignacio Hernandez-Ros]

Use XBRL tuples to enforce your content model using XML Schema constraints like choice, sequence and all.

Now the problem is reduced to enforce one tuple to exist in the instance. There is no a clean solution to this problem because that requires youto create a new element (in a schema) that extends by restriction the xbrli:xbrl element as it is defined in the xbrl-instance-2003-12-31.xsd schema. You can define the content model of that new element but the root container will no longer be xbrli:xbrl but your newly defined element.

[Kamal Karunaratna]

Thanks a lot for the reply. Looks like this is the answer.

As far as you know, is there any reason as to why this is not to be considered a valid XBRL solution?

Some people suggest that this is not a valid XBRL usage.