What is XBRL Versioning?
XBRL Versioning is a communication tool, in the form of
a Versioning Report. Versioning reports are usually created by the taxonomy
development team during the process of publication of a new taxonomy version.
That report is used to communicate the differences
between two XBRL Taxonomies or two versions of the same XBRL Taxonomy. The
original DTS is referred to as the ‘From DTS’ and the second one as the ‘To
DTS’. (Note that the word “Taxonomy” is often used synonymously with “DTS”)
The XBRL Versioning process compares the ‘To DTS’ with
the ‘From DTS’ and shows, by way of a report, what has changed and, provided the
taxonomy developer has provided the necessary descriptive information, why the
change has been made. A DTS contains taxonomy schemas and linkbases, but no
instance document; therefore, this process does not compare instance documents.
Why is XBRL Versioning important?
XBRL Versioning is important because it minimises the
costs associated with migrating from one DTS to another. Updating and revising
DTSs are common features of any XBRL implementation and therefore XBRL
Versioning is a highly sought after tool as it will provide a well documented
trail of the changes associated with a migration to a new DTS.
Who can use XBRL Versioning?
Taxonomies need to change over time to meet new requirements that may
emerge. Therefore, XBRL Versioning is
helpful for various users working with the XBRL data format.
These users include:
·
Taxonomy developers:
o
To communicate the
changes that have been made from the previous version to the next version of an
XBRL taxonomy.
o
In case of extension
taxonomies, to evaluate the impact of migrating to a new release of the base
taxonomy.
·
Instance creators:
o
To adopt the changes
in the mapping process for the creation of the XBRL reports. Thanks to the
versioning report, this process could be done almost automatically.
·
Instance receivers:
o
To evaluate the impact
on the storage systems and internal applications.
·
Taxonomy reviewer:
o
To check if all
business and technical change requirements have been integrated into the new
version of the DTS.
·
Taxonomy analyst:
o
To compare two
different extension taxonomies of the same base taxonomy, e.g. IFRS or
COREP/FINREP, in order to analyse the distinctions.
What is an XBRL Versioning report?
The versioning report lists the differences between two
DTSs, and also includes human readable documentation about the changes.
In the most common use case, the two DTSs will represent two consecutive
versions of the same taxonomy.
Which tools are available?
At this stage of the development phase (PWD 1.0), only
one tool is available.
How can I collaborate?
·
By trying to use the
XBRL Versioning Specification (XVS).
·
By looking at how XVS
fits in your business requirements.
·
By sending us your
feedback about the results of your evaluation.
Your feedback is essential for us to ensure that the XBRL Versioning
Specification meets the real business needs of XBRL projects around the globe.
Therefore we summarised questions to get your view on specific versioning
topics.
Please add your comments to the questionnaire document and send it to
the following email address: versioning-feedback@xbrl.org.
Deliverables of the Versioning Working Group (VWG)
·
Versioning
Specification Requirements
Main requirements for versioning are:
o
The detection of changes
between two taxonomies at the concept, relationship and resource level.
o
The documenting of
these changes.
o
The capture of
versioning information during and after the development phase of a taxonomy.
o
A standardised syntax
to be processed by XBRL software, i.e.
§
for the automatically
adoption of mapping processes.
§
for the creation of a
human readable versioning report.
·
XBRL
Versioning Specification
o
Description
o
Definition of the
information to be compared
o
Rules of
correspondence
§
Description of conditions that must be satisfied in order to
consider concepts, relationships or resources as
correspondent.
§
They are used to help
versioning processors determine what information item in the To DTS must be
compared with an information item in the From DTS (and vice versa)
o
Content model
§
The XVS specification
separates the content of the versioning report from the
syntax. The Diff Events are just input to the versioning report.
o
Syntax
- The syntax to be used
to express the versioning report is still under discussion within the
VWG. Possible syntaxes being discussed include: “raw” XML, a linkbase,
an XBRL instance document. The current alternatives being evaluated are:
1) an XBRL instance (using a Versioning Taxonomy), 2) a linkbase
according to the generic linkbase specification, 3) an XML Schema
document and 4) an XML instance according to a schema, but without the
overhead of irrelevant XBRL metadata.
·
XBRL Infoset
o
is a description of
the content of a DTS without any reference to the XBRL syntax.
o
is referenced by the
XBRL Versioning Specification to identify each property of an information item
in a DTS.
o
is recommended by the
Versioning Working Group to be used to identify the information that should be
compared.
o
as an
object model, can be integrated in XBRL software that
supports XBRL versioning.
o
is expected to be used
in other areas of the development of XBRL.
o
does not include a
description for instance documents.
·
Conformance
suite
- Test cases
- XSLTs
- Syntax for test cases
·
XBRL
Versioning Specification on Dimensional Taxonomies
- The VWG is still
working on a specification to handle dimensional taxonomies and expects
to release a separate document to address the specific issues involved
with these types of taxonomy in due course.