What Inline XBRL is, for preparers
What Inline XBRL is, how a tagged set differs from a PDF of the statements, why regulators want tagged data, and how custom lines keep tags consistent.
By Achekam · · 4 min read · For Accountants & audit firms in South Africa, Nigeria, Kenya
For years the end product of a statements engagement was a PDF: a faithful picture of the printed set, easy to e-mail, easy to read and useless to a computer. A regulator or analyst who wanted the revenue figure from a thousand PDFs had to find it a thousand times.
Inline XBRL keeps the document a person reads and adds a layer software can read. For preparers in South Africa, Nigeria and Kenya, it is worth understanding what that layer is, even where no local rule yet requires it for a particular client.
One document, read by people and by software
XBRL International describes XBRL as the global standard that powers digital reporting, making business reporting computer-readable so that business data is easy to find, access and analyse. In an XBRL report, it explains, each fact is digitally tagged so that software can recognise it and users anywhere can extract and analyse it efficiently.
Inline XBRL, or iXBRL, answers a practical tension: regulators want data, while companies and their readers want a report. XBRL International defines iXBRL as an open standard that enables a single document to provide both human-readable and structured, machine-readable data. One file does both jobs.
Tags embedded in a web page
The mechanism is easy to picture. XBRL International explains that iXBRL takes the HTML standard used for web pages and embeds extra tags into it, giving meaning to the figures and statements in a form a computer can understand.
Open an iXBRL file in a browser and it looks like a set of financial statements, with headings, tables and notes. Behind the visible revenue figure sits a tag stating what the figure is, which entity and period it belongs to and the unit it is expressed in. The tag takes its meaning from a taxonomy, a dictionary of concepts, explained in the IFRS Accounting Taxonomy and tagging.
Why regulators ask for tagged data
XBRL International states that iXBRL lets companies prepare statements that provide the structured data regulators and analysts require, while preparers keep full control over the layout and presentation of their report.
That combination explains the appeal. A register or tax authority receives filings it can check and analyse by machine: comparing years, spotting missing items, adding up sectors. The company still decides how its report looks, and nobody is forced into a rigid form that strips the statements of their notes and context.
For the firm, the consequence is that figures are no longer only read; they are processed. An error a human reader might pass over, such as a balance on the wrong line or a sign the wrong way round, becomes a data error that software repeats in every analysis built on it.
PDF statements and tagged statements side by side
| PDF set | iXBRL set | |
|---|---|---|
| Who can read it | People | People and software |
| What a figure means | Whatever its heading says | Its heading plus a defined concept |
| Getting data out | Retyping or text recognition | Directly, from the tags |
| Layout | Set by the preparer | Still set by the preparer |
| Effect of a mapping error | Misleads the reader | Misleads the reader and every system using the data |
In Achekam, staff can download the statements as an A4 PDF made on Achekam's server, and issuing stores the final PDF with a fingerprint and locks that version. That issued PDF is the record of what the partner signed.
For South African clients, Achekam can also turn a set of statements or a trial balance into an iXBRL file, check it with its own validation and pack it in a ZIP file with the validation report. Its built-in taxonomy is a partial list Achekam wrote, so only test packs can be made with it. A production pack is refused until the official CIPC taxonomy package has been uploaded and approved, and Achekam does not file with CIPC. Achekam does not produce iXBRL for Nigerian or Kenyan clients. The South African steps are in CIPC iXBRL test packs.
Keeping tags consistent when custom lines are added
Clients like their own line items. A transport business wants "Fuel" and "Tyres" on the face of the income statement; a private school wants "Fee income" rather than "Revenue". Every custom line raises a tagging question: which concept does this figure represent?
In Achekam, a firm can add its own statement lines and groups and change the wording of any row title, and later builds keep those choices. Each custom line still totals into a standard line, so notes, cash flow and iXBRL tags stay consistent. The client gets the presentation it wants, and the figure underneath keeps its link to a standard concept. A school's "Fee income" is still revenue as far as the data is concerned.
Where to read more
XBRL International's page on iXBRL explains the open standard that lets one document carry both readable statements and structured data, and where regulators require it.
The practical lesson for a preparer is that the quality of a tagged report is decided long before tagging, in mapping and presentation. Put each account on the right line, keep custom lines tied to standard ones, and resolve every placeholder. Do that, and the tags have something sound to describe.
For a firm that has never tagged a set, a sensible first step is a dry run on one straightforward client: map the trial balance carefully, build the statements, and look at each line with the question "which concept is this?" in mind. The lines that are hard to answer are the ones that will cause trouble at filing time, whatever the tool.
General guidance only, not advice on your own circumstances. Tax and payroll rules change: check the current position with the authority or your adviser.
