What is the Boston Question? Why doesn XBRL use a relatively deep tree structure to represent information with XML?
The Boston question is perhaps the most commonly asked question about XBRL, especially by those familiar with more traditional uses of XML. At its most succinct, the Boston question is why XBRL does not make greater use of the XML content model. Traditional XML, by enabling users to place data in tree structures, gives tree traversal and manipulation algorithms a data structure that is relatively computationally efficient. Because of the extensibility required of XBRL and because of the requirement that XBRL facts can be reported on their own or in any order, this deep nesting of content in a tree structure is not feasible. XBRL does, however, facilitate the representation of relationships among concepts. Instead of using the XML tree structure, XBRL uses linkbases to express relationships between concepts.
The Boston question is perhaps the most commonly asked question about XBRL, especially by those familiar with more traditional uses of XML. At its most succinct, the Boston question is why XBRL does not make greater use of the XML content model. Traditional XML, by enabling users to place data in tree structures, gives tree traversal and manipulation algorithms a data structure that is relatively computationally efficient. Because of the extensibility required of XBRL and because of the requirement that XBRL facts can be reported on their own or in any order, this deep nesting of content in a tree structure is not feasible. XBRL does, however, facilitate the representation of relationships among concepts. Instead of using the XML tree structure, XBRL uses linkbases to express relationships between concepts. The relationships expressed in these linkbases are slower to process using the current generation of XML tools than are data structures that leverage XML’s tree-based data structure
