XBRL International has announced the release of an XBRL version 2.1 Specification Working Draft and a 60-day public review period preliminary to consideration as a final XBRL 2.1 Recommendation. XBRL "provides users with a standard format in which to prepare business reports that can subsequently be presented in a variety of ways. It supports software vendors, programmers, and intermediaries in the preparation and distribution process and end users who adopt it as a specification to enhance the creation, exchange, and comparison of business reporting information. Business reporting includes, but is not limited to, financial statements, financial information, non-financial information, general ledger transactions, and regulatory filings such as annual and quarterly financial statements." The prose portion of the version 2.1 specification has expanded by 54 pages, including "many more usage examples, code fragments from the defining XML schemas, greater detail about pre-existing XBRL 2.0 features, and detailed explanations of the new features. Domain experts and application developers can now define the handling of new relationships not defined by XBRL itself; new relationships allow taxonomy authors to precisely connect taxonomy definitions to authoritative definitions and other supporting documentation. Calculation links have been made more powerful through a mechanism for expressing relationships between items in different contexts, meeting a key request from builders of complex financial reports."

XBRL Version 2.1 Bibliographic Information

Extensible Business Reporting Language (XBRL) 2.1. Public Working Draft of 2003-04-23. 93 pages. XBRL International Inc. Edited by Phillip Engel (KPMG LLP), Walter Hamscher (Standard Advantage), David vun Kannon (KPMG LLP), and Hugh Wallis (Hyperion Solutions Corporation). Contributors: Charles Hoffman (UBmatrix LLC Campbell Pryde (KPMG LLP), and Geoff Shuetrim (KPMG LLP). Version URLs: http://www.xbrl.org/2003/XBRL-WD-2003-04-23.doc (Word); http://www.xbrl.org/2003/XBRL-WD-2003-04-23.pdf (Acrobat PDF). Separate provision of XML Schemas. All components, along with non-normative samples and certain schemas are available in a single ZIP format archive.

XBRL Version 2.1 Working Draft Abstract

XBRL is the specification for the Extensible Business Reporting Language. XBRL allows software vendors, programmers, intermediaries in the preparation and distribution process and end users who adopt it as a specification to enhance the creation, exchange, and comparison of business reporting information. Business reporting includes, but is not limited to, financial statements, financial information, non-financial information, general ledger transactions, and regulatory filings such as annual and quarterly financial statements.

This document defines XML elements and attributes that can be used to express information used in the creation, exchange, and comparison tasks of business reporting. XBRL consists of a core language of XML elements and attributes used in XBRL instances as well as a language used to define new elements and taxonomies of elements referred to in XBRL instances, and to express constraints among the contents of elements in those XBRL instances.

The XBRL Framework

The main ideas in the XBRL conceptual framework are items and taxonomies; taxonomies in turn consist of schemas and linkbases.

An item is meant to correspond to a fact -- often but not necessarily a numeric fact -- that is being reported with respect to a given period of time about a given business entity. For example, the fact that the company whose ticker symbol is SAMP reported revenues of USD 7m for the year 1998 is an item. This is an example of a numeric item... XBRL defines a syntax in which many different kinds of facts can be represented and their contexts defined in such a way that software applications can efficiently and reliably find, extract, and interpret relevant facts in their appropriate contexts.

An important part of the XBRL framework is the concept of an element and its relationships to other elements within a taxonomy. In XBRL, the notion of a taxonomy element is represented by an element within an XML Schema. An example taxonomy for the purposes of the current specification is the particular taxonomy consisting of elements that correspond to well-defined concepts within the US Generally Accepted Accounting Principles (GAAP) when those principles are applied to Commercial and Industrial (C&I) companies. For example, concepts of 'Accounts Receivable Trade, Gross', 'Allowance for Doubtful Accounts', and 'Accounts Receivable Trade, Net' may be associated with different elements in this particular taxonomy.

Relationships among the elements in a taxonomy, and relationships between the taxonomy and information outside of XBRL, are represented by linkbases using XML Linking Language. A linkbase consists of one or more 'extended links,' which in turn consist of arcs, locators and resources; arcs with different 'arcroles' have different semantics.

XBRL imposes syntactic restrictions that are not captured in XML Schema. XBRL instances must validate against all of the taxonomy schemas and XML schemas to which it refers, and taxonomy schemas and linkbases must validate against the schemas to which they refer... A definition linkbase describes constraints over the content of items..." [adapted from section 3]

From the Announcement

The eXtensible Business Reporting Language (XBRL) allows the platform independent definition, exchange and dissemination of corporate reporting concepts and documents. It can be used to express a wide range of reports and disclosures including financial statements, internal management information, regulatory returns, statistical reports and credit filings. XBRL International is a non-profit consortium whose members include over 220 leading organisations concerned with the business information supply chain. XBRL has been widely recognised as an important component in the improvement of corporate transparency. The XBRL 2.1 Working Draft Specification was been developed in response to calls from software vendors for greater clarity in order to ease implementation and ensure interoperability as the push for reform in corporate reporting accelerates.

The XBRL 2.0 Specification, available to the market since December 2001, and all XBRL taxonomies developed in conformance with the XBRL 2.0 Specification, remain valid and continue to be supported by many software vendors. XBRL applications use XBRL taxonomies that consist of definitions of financial and business reporting terms expressed in XML Schema, along with rich networks of relationships among those terms, expressed using XML Linking Language. Those already developing taxonomies and applications that are fully XBRL 2.0 compliant may, but need not, consider only the following change in order to be XBRL 2.1 compliant: an indication on each taxonomy definition to indicate whether it is meant to denote a fact reported as of a point in time, or over a period of time. All other aspects of XBRL taxonomies and instance documents can be converted to XBRL 2.1 through automated means.

Benefits of the more detailed technical exposition of existing features in XBRL version 2.1: There have always been restrictions on what is a meaningful taxonomy schema, meaningful linkbase, and meaningful instances. In the past many of these criteria were implicit; these criteria are now part of the specification and either enforced using XML Schema requiring no new code to be written, and in other cases will allow vendors to more easily write consistent validation code. Examples of these technical enhancements include a detailed exposition of handling variable precision numbers, prohibitions on certain kinds of loops in relationships, and prohibition of duplicated data in instances. The meaning of calculation links and their ability to express relationships between items in different tuples has been specified precisely.