How to set correct fact signing in ESEF

In ESEF (or any other inline XBRL report), you report both a human-readable report and machine readable tags. In the human readable report, you can report positive or negative numbers, and usually from the context it is clear to the reader how to interpret these numbers. However, there could be situations where there is ambiguity. In the machine readable version, no ambiguity is allowed to exist, and you have to make sure the signs of all reported values are correct.

Any type of expense for example can be shown as a negative number in the human-readable report: as it is an outflow it can make sense to represent this as a negative number. However, since the tag in the XBRL taxonomy already states it is an expense, reporting a negative number in the XBRL fact would actually represent an inflow.

The rule of thumb for setting the correct signs for XBRL fact values is to look at the wording and balance of the concepts in the taxonomy. In principle the default should be to always use positive values in the XBRL. If you report a negative value, that means the reported value differs from what would be expected for this concept.

Let's take a look at some examples to show how the sign in the XBRL fact can deviate from the sign in the readable report:

Finance costs is reported as a negative value in the human-readable report. In the context of the Profit or loss, it is an outflow, so this makes sense. However, looking at the wording and balance of the Finance costs tag, you see that this already indicates a cost, and the fact value should be positive.

Other finance income (cost) is also reported as a negative value in the human-readable report, as it is an outflow just as well. However, in this case you can see from the wording of the tag that it expects an income. In this case it is not an income, but a cost, and therefore the XBRL value should be negative.

Adjustments for finance income (cost) is reported as a positive value in the human-readable report, since in the context of the Cash Flow statement this is the case. However, since the tag again assumes adjustments for finance income, but this is actually adjustments for finance cost, a negative fact value should be reported.

For completeness, we can also look at the simple situation of Profit (loss) before tax. Since in this case a profit is reported, this is a positive value in both the human-readable version and the XBRL fact.

When to modify the default sign behavior?

First of all, it is important to understand the above, and understand the desired situation. For some cases, this will be already the case. Because of the ambiguity in the readable version, we cannot with certainty set the XBRL fact to the correct sign, and you might need to control this in Tangelo.

A good indication that the signs of the fact values in your report are not set correctly is if you are getting calculation inconsistencies. However, there can be facts that are not a part of a calculation, and it is worthwhile to check all.

To control the sign of the XBRL facts in the report, you can use the "Concept is negative" property in Tangelo. This is available on the row level for if you want to consistently set a certain sign for the entire row, or on the cell level if you want to set this for a specific year. Using this property you can explicitly set the fact value to either positive or negative.

See the table below on how to use this attribute to accomplish specific results for the XBRL fact value:

Credit (or no balance set in the taxonomy)

Debit

Further reading

ESEF Reporting Manual, Guidance 1.6: https://www.esma.europa.eu/sites/default/files/library/esma32-60-254_esef_reporting_manual.pdf

https://www.corporatings.com/blog-post/best-esef-practices-how-to-avoid-of-sign-errors