Comparability Task Force
Phase 1 Deliverable - Feedback requested
Comparability Business Requirements 1.0 - August 15, 2012
Comparability enables XBRL instance documents, even from different taxonomies, to be compared and consumed. This document is a tool for defining comparability requirements in detail, from a business point of view. Two versions of the document are being provided for convenience:
The Comparability Task Force would like to receive feedback on this document at the following email address: comp-feedback@xbrl.org
Task Force Information
Summary
One of the driving forces behind the success of XBRL has been its inherent ability to automate and streamline the information systems which process, analyse, and compare data expressed in XBRL. The increasing volume of XBRL data being accumulated at a global level is inspiring ever-more creative ways of tapping into the full potential of XBRL, especially as it relates to issues of data comparability. This demand for increasingly sophisticated ways of comparing XBRL data has brought focus on some improvements which need to be addressed when applying XBRL data comparisons across international, jurisdictional, and taxonomy boundaries.
In the discussion document, data comparability was one of the three primary goals, and the XSB received an extensive amount of feedback on the objectives associated with this goal. By formalising and enhancing data comparability frameworks at a global level, we can look forward to increased adoption and more varied applications of XBRL.
Overview
A more detailed description of the comparability use cases is as follows:
•Base Comparison - The actors in this use case are Companies A and B, who wish to provide XBRL reports using 2 different taxonomies - IFRS and US GAAP, respectively. The 2 instance documents are made available to another actor on the consumption side, Bloomberg, who wishes to perform a comparison between the data in the 2 instance documents. In order to accomplish that effectively, Bloomberg must be able to understand and bridge the differences between the IFRS and US GAAP taxonomies, and does so by consuming Assertion Sets which are provided by a third actor, the Assertion Provider. The Assertion Provider provides Assertion Sets by analyzing the differences between 2 taxonomies - in this case IFRS and US GAAP - and by defining a single, discrete Assertion for cases where there is a worthwhile point of comparison between the two taxonomies.
•Extension Comparison - The actors in this use case are Companies A and B, who wish to provide XBRL reports using the same taxonomy, but whose taxonomies differ from each other because of the unique taxonomy extensions provided by each company. Companies A and B make both their XBRL instance documents and their respective taxonomy extensions available to an actor on the consumption side, Bloomberg, who wishes to perform a comparison between the data in the 2 instance documents. In order to accomplish that effectively, Bloomberg must be able to understand and bridge the differences between the 2 taxonomy extensions, and does so by consuming Assertion Sets which are provided by a third actor, the Assertion Provider. The Assertion Provider provides the Assertion Sets by analyzing the differences between the 2 taxonomy extensions, and by then defining a single, discrete Assertion for cases where there is a worthwhile point of comparison between the two taxonomy extensions.
•Inference Comparison – The actors in this use case are Companies A and B, who wish to provide XBRL reports using two different taxonomies - IFRS and EDINET, respectively. The 2 instance documents are made available to another actor on the consumption side, Bloomberg, who wishes to perform a comparison between the data in the 2 instance documents. In order to accomplish that effectively, Bloomberg must be able to understand and bridge the differences between the IFRS and EDINET taxonomies, but unlike the first use case there are no assertion sets available which directly bridge the gap between IFRS and EDINET. Rather, there is an intermediate taxonomy - US GAAP in this case - for which assertion sets do exist between it and IFRS, and between it and EDINET. There are 2 actors, Assertion Provider and Assertion Provider 2, who analyzes the difference between IFRS and US GAAP (performed by Assertion Provider), and the differences between US GAAP and EDINET (performed by Assertion Provider 2), and by consuming these 2 assertion sets Bloomberg is able to perform a meaningful comparison between instance documents that are based on taxonomies which may not have assertion sets directly available between them.
To sign up for this initiative please send an email to comparability@xbrl.org with a specific request to join the initiative.
