XBRL

Definition

XBRL (eXtensible Business Reporting Language) is an open standard for exchanging business information. XBRL provides a semantic framework to encode the information usually communicated in Business Reporting. Business data submitted as XBRL filings, that is, where information is annotated according to a predefined schema can be processed programmatically by computers. Extensibility is a very important aspect of the standard as the nature of business reporting requires is open ended. The XBRL Specification is developed and published by XBRL International.

Technology and Specifications

XBRL is primarily based on XML and associated technologies: XML Schema, XLink and XPoint. XML is a very general format, XBRL is actually a very constrained version.

• The Base XBRL Specification is 2.1
• The Inline XBRL Specification is 1.1

iXBRL (Inline XBRL) is a development of XBRL in which the XBRL metadata are embedded in an HTML document, e.g., a published report and accounts. It requires the HTML document to be well-formed but does not otherwise specify the required XML format. Typically, iXBRL is implemented within HTML documents, which are displayed or printed by web browsers without revealing the XBRL metadata inside the document. The specification does, however, provide a normative schema which requires that any schema-valid iXBRL document should be in XHTML format.

Terminology

• An XBRL Instance (or XBRL File) contains the business facts being reported. An instance along with a taxonomy forms a complete submission (report or filling).
• An XBRL Taxonomy defines metadata about what the facts mean and how they related to each other. It is the analog of a class specification in OOP, whereas an instance is a concrete object conforming to that taxonomy. A taxonomy may include formulae and validation rules.
• An Business Concept (also Business Element) is any abstract notion that describes an aspect of a business entity (e.g., an asset)
• A Business Fact is a literal value that is tagged in a given XBRL Context: Minimally, a Fact is a concrete instance of a Business Concept (aspect). It concerns a concrete Business Entity, a given time point or Period and is expressed in a given Unit.
• XBRL Context. Entity and report-specific information (reporting period, segment information, and so forth) required by XBRL that allows tagged data to be understood in relation to other information. More aspects can be created and provided along a fact to provide further context.
• A Conformance suite is a set of tests
• A processor is an application that can parse an instance.
• An XBRL Document contains one or more XBRL Instances
• Qname (Qualified Name) is the unique XML name of each accounting definition

Glossary

• Abstract. An attribute of an element to indicate that the element is only used in a hierarchy to group related elements together. An abstract element cannot be used to tag data in an instance document
• Attribute. A property of an element such as its name, balance, data type, and whether the element is abstract.
• Balance. An attribute of a monetary item type designated as debit, credit, or neither; a designation, if any, should be the natural or most expected balance of the element - credit or debit - and thus indicates how calculation relationships involving the element may be assigned a weight attribute (-1 or +1)
• Calculation relationships. Additive relationships between numeric items expressed as parent-child hierarchies
• Axis Default Relationship. The dimensional relationship indicating that the table axis has a default domain member
• Axis Domain Relationship. The dimensional relationship indicating that the table axis has members drawn from a domain
• Decimal. Fact attribute used to express the number of decimal places to which numbers have been rounded
• Domain. An element that represents an entire set of other elements; the domain and its members are used to classify facts along the axis of a table.

Taxonomy Schema

A taxonomy schema is an XML schema document (file). The schema must ultimately extend the XBRL instance schema document and typically extend other published XBRL schemas on the xbrl.org website.

Taxonomy schemas define Item and Tuple "concepts" using <xsd:element> elements.

Concepts provide names for the fact and indicate whether or not it is a tuple or an item, the data type (such as monetary, numeric, fractional, or textual), and potentially more metadata.

Items and Tuples can be regarded as "implementations" of concepts, or specific instances of a concept. A good analogy for those familiar with object oriented programming would be that Concepts are the classes and Items and Tuples are Object instances of those classes. This is the source of the use of the "XBRL instance" terminology. In addition to defining concepts, taxonomy schemas reference linkbase documents. Tuples instances are 1..n relationships with their parents; their metadata is simply the collection of their attributes.

Extensibility

Besides the creation of additional modules, XBRL International supports several methods for continuing expansion of shared XBRL functionality.

• Link Role Registry This registry, hosted at xbrl.org, collects link roles and arc roles to promote reuse across taxonomies.
• Functions Registry This registry collects XPath functions for reuse in formula linkbases.
• Transformation Rules Registry This registry collects common transforms used to convert human-readable data in Inline XBRL documents (e.g. "1st January 2016") into the formats required by XBRL ("2016-01-01").

Issues and Challenges

• Collisions (multiple values for the same concept)

See Also

• SDMX

References

• SEC XBRL Glossary of Terms
• ESEF Reporting Manual, Preparation of Annual Financial Reports in Inline XBRL
• Wikipedia