The IFRS Accounting Taxonomy and tagging
What the IFRS Accounting Taxonomy is, how a figure in a client's statements comes to carry a tag, and why mapping decides the quality of the tags.
By Achekam · · 4 min read · For Accountants & audit firms in South Africa, Nigeria, Kenya
Most preparers meet the IFRS Accounting Taxonomy sideways. A regulator announces that filings must be tagged, a screen asks for an "element" for a line, and suddenly the vocabulary of the statements has a second layer that nobody in the firm has had to think about.
The idea underneath is simple. Every figure in a set of statements already means something: revenue, trade receivables, depreciation. Tagging writes that meaning down in a form software can read, using a fixed list of names. The IFRS Accounting Taxonomy is that list for statements prepared under IFRS Accounting Standards.
A dictionary of concepts
XBRL International explains that the concepts against which figures in an iXBRL report are tagged, for example "ifrs:Revenue", are drawn from a dictionary of concepts known as a taxonomy. It also explains that standard-setters and regulators build these dictionaries to define exactly the information they need.
The IFRS Foundation states that the IFRS Accounting Taxonomy includes elements for tagging statements prepared in accordance with IFRS Accounting Standards, and that tagging makes the information computer-readable so investors can extract, compare and analyse it more efficiently. XBRL International's own sample IFRS report is tagged using the IFRS taxonomy, published by the IFRS Foundation.
Think of each element as a defined term with a fixed identity. One company calls a line "Turnover" and another calls it "Sales"; anyone reading the tagged data sees one concept, because both figures carry the same element.
What the taxonomy reflects
The IFRS Foundation states that the taxonomy reflects the presentation and disclosure requirements of IFRS Accounting Standards and includes elements from accompanying materials such as implementation guidance and illustrative examples.
For a preparer that has a useful consequence. When a line exists in the statements because a standard requires it, there is very likely an element waiting for it. Before deciding that a client's line is unique, look for the standard concept it belongs to.
Regulators' own taxonomies
Because regulators build taxonomies to define the information they need, a filing regime may prescribe a dictionary that adds to, narrows or differs from the IFRS one. Before tagging anything for a regulator, establish which taxonomy that regulator requires and which version it currently accepts. Answer that question filing by filing; what one register requires says nothing about another.
For South African firms preparing iXBRL for CIPC, the practical steps are covered in CIPC iXBRL test packs.
From mapped line to tag
A figure reaches its tag in two steps. First, the trial balance account is mapped to a line in the statements. Second, that line is associated with a taxonomy element. If the first step is wrong, the second repeats the error faithfully in machine-readable form. A loan to a director mapped into trade receivables becomes a tagged trade receivables figure that every user of the data will take at face value.
So the quality of tagging rests on the quality of mapping. In Achekam, suggestions for where each trial balance line belongs come from the file's own mapping column, earlier mappings, AI or keyword rules, and no suggestion becomes an approved mapping until a person approves it. Without an AI key, keyword rules are used and labelled as such (Financial Intake, then Trial Balances).
Firms can also add their own statement lines and groups and reword any row title, and later builds keep those choices. Every custom line still totals into a standard line, which keeps the notes, the cash flow statement and the iXBRL tags consistent. A client who insists on showing "Fuel and oil" on its own line gets that line, and the figure keeps its connection to the standard concept above it. When a line truly has no standard home, the options are described in XBRL extension elements.
Where Achekam's iXBRL stops
Achekam's iXBRL output is for South African clients. It turns a set of statements or a trial balance into an iXBRL file, checks it with Achekam's own validation and packs it in a ZIP file with the validation report. The built-in taxonomy is a partial list Achekam wrote, so it can only make test packs; a production pack is refused until someone uploads and approves the official CIPC taxonomy package, and Achekam does not file with CIPC.
Achekam does not produce iXBRL for Nigerian or Kenyan clients. The mapping discipline below still applies to any tagging those firms do with other tools.
Getting mapping right first
Before any figure is tagged, the mapping should survive a reviewer's questions:
- Every account sits on the line that describes what it is, not the line that made the draft balance quickly.
- Accounts whose character changed during the year, such as a loan that fell due or a deposit that became revenue, are mapped to where they belong at year end.
- Custom lines added for presentation roll up into the standard line a reader would expect.
- Approved mappings were approved by someone who looked at the account, not accepted in bulk.
- Renamed row titles still describe the same concept as the line beneath them.
The IFRS Foundation's IFRS Accounting Taxonomy page explains the set of elements used to tag IFRS statements so that the information becomes computer-readable. For what the tagged document itself looks like, see what Inline XBRL is.
Tagging is the last link in a long chain. A clean element attached to a mis-mapped figure is still a wrong figure, now one that software will copy into every comparison. Spend the effort on mapping and the tags will have something sound to describe.
General guidance only, not advice on your own circumstances. Tax and payroll rules change: check the current position with the authority or your adviser.
