Standard XBRL 2.1 feature that an instance document (or inline XBRL document) may refer to facts in multiple taxonomies.
In a fictitious sustainability report, the revenue figure is reported against the financial taxonomy (“xii”). This is representative of the real world situation where the revenue is prepared for the financial report and later duplicated in to the sustainability report:
However, the revenue per staff figure is not defined in the financial report but is required as part of the sustainability disclosure. So here it is reported against the sustainability taxonomy (“dsd-example-10”):
Inline Viewer – XBRL International Inc. Sustainability Disclosure