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combination of the two elements that are available in the ESEF taxonomy. The
extension taxonomy element ‘issued capital and share premium’ shall be anchored to
these two elements, indicating that it is wider in scope than these two elements.
The obligation to anchor to “narrower” elements exists not only where the extension is
exclusively a combination of core taxonomy, but rather whenever there is a combination
of two or more taxonomy elements. For instance, if the issuer needs to create an
extension for 'Share capital, Share Premium and [other entity specific reserve for which
there is no tag available in the core taxonomy]', it is mandatory to anchor that extension
to 'Issued capital' and 'Share premium'.
1.5 Use of line items or domain members
Guidance 1.5.1 Determination of whether a disclosure should be marked up with
a line item or a domain member [last updated: July 2021]
XBRL taxonomies contain line items and domain members which are both elements
used to mark up disclosures. Line items normally represent the accounting concepts
being reported. They are used to mark up numeric accounting information as well as
qualitative (non-numeric) disclosures. Line items are stand alone, but can be used
either individually or in a table (in combination with axis and axis members).
Axes and domain members (also sometimes referred to as ‘axis members’ or
‘members’) are elements that are mainly used to disclose information for line items from
different aspects, such as the disaggregation of the information for line items into
different product types, categories, classes and maturities. The axis is the specific
aspect being considered. An axis includes one or more components (called members)
which share the common accounting or economic meaning defined by that axis.
For example, ‘revenue’ as a line item can be used to tag numbers that refer to various
operating segments. In this case the ‘segments [axis]’ dimension can be applied to
differentiate between revenues of the cars segment, using the element ‘cars [member]’
and of the motorcycles segment using the element ‘motorcycles [member]’. It is
important to note that members and axes cannot be used on their own, but are used
together with line items to mark up disclosures. Moreover, the same piece of
information can be tagged using a line item only or a line item together with a dimension
member. For example, the item ‘land and buildings’ in the statement of financial position
can be marked up using the line item ‘land and buildings’ or using the line item ‘property,
plant and equipment’ in conjunction with the domain members ‘land and buildings
[member]’ of the axis ‘classes of property, plant and equipment [axis]’.
In order to facilitate consistent use of line items and domain members despite the
flexibility offered by the XBRL standard, extension elements should be defined as line
items unless the applicable taxonomy envisages in a particular statement or disclosure
the use of domain members.
For example, the ESEF taxonomy contains two elements with the name ‘issued capital’,
one is a line item and one is a domain member. The applicable taxonomy envisages