What is the multiple rollup issue?
Many tools that have been designed to build XBRL taxonomies represent the relationships built into taxonomies using a tree representation. This tree representation restricts the way in which relationships between taxonomy concepts can be used. For example, cycles in the relationships are ruled out by this design limitation in the early XBRL software. If concept A was a parent of concept B then B could not be defined to be a parent of concept A. More interestingly perhaps concept B could not be associated with multiple parents. This caused early taxonomy developers much anguish because, to work with the XBRL taxonomy development tools they had to define the same concept many times in a taxonomy. This was more work and it reduced the comparability benefits of using XBRL in the first place. To produce taxonomies where elements have multiple parents, it has been necessary to work outside of the current generation of XBRL software tools for XBRL taxonomy creation.
Many tools that have been designed to build XBRL taxonomies represent the relationships built into taxonomies using a tree representation. This tree representation restricts the way in which relationships between taxonomy concepts can be used. For example, cycles in the relationships are ruled out by this design limitation in the early XBRL software. If concept A was a parent of concept B then B could not be defined to be a parent of concept A. More interestingly perhaps concept B could not be associated with multiple parents. This caused early taxonomy developers much anguish because, to work with the XBRL taxonomy development tools they had to define the same concept many times in a taxonomy. This was more work and it reduced the comparability benefits of using XBRL in the first place. To produce taxonomies where elements have multiple parents, it has been necessary to work outside of the current generation of XBRL software tools for XBRL taxonomy creation. Note however that these ki
