You can use dimensional tagging when facts need additional context applied beyond the concept and date. Dimensional tagging uses axes and members to add this additional layer of context to an XBRL fact.
This article describes the process of dimensional tagging using the Statement of Changes in Equity as an example.
Example: Statement of Changes in Equity
We use a Statement of Changes in Equity as the example throughout this article.
The Statement of Changes in Equity differs from the other main financial statements because each line item is separated into constituent values that amount to the total in the final column. To differentiate the constituent values in each column, you’ll apply a dimension to each of the facts in addition to the concepts and dates. You’ll do this by adding an Axis and Member.
You can apply concepts, dates, and axis/members in any order, but it is a best practice to apply the concept and date first.
Tagging with an Axis
The document has a Statement of Changes in Equity that we need to dimensionalize to show the difference among the values of each column. You do this by first adding an Axis.
Highlight all the number cells that you want to dimensionalize in the table except the Total column. For our example, we highlight all the number cells in the Balance line. In the XBRL Detail Tagging dialog box, click the Add Axis button.
NOTE: You can tag cells individually or you can select multiple cells to tag at the same time.
The XBRL Concept Search box opens and gives you a list of axes to choose from. For our example, select the Equity classes [Dimension] axis and click the green Accept button to apply to the selected cells.
You can also add an Axis by clicking the Manage Dimensionality button. The axes and members available for the selected concept are listed under Available Members. This allows you to make sure you are not selecting an incorrect Axis, which may cause an error when you generate.
IMPORTANT: The number of dimensions allowed (both Axis and Member) depend on the concept you select.
Tagging with a Member
Now you need to tag each column with a Member for the Axis. Select one column at a time, then select Search Domains / Members in the XBRL Detail Tagging window to search for a Member.
Expand the Available Members sections to look for the correct member. Click the green plus sign next to the Member you want to use. Click outside the XBRL Detail Tagging dialog box to close it. The Member you selected is applied to the fact.
Normally, you do not tag the total column with an Axis or Member because it is the consolidated total of each of the equity values.
NOTE: If there are additional values that appear on your Equity Statement (such as multiple classes of stock, adjustments, etc.), you may need to apply more than one Axis to appropriately differentiate the concepts.
Your fact is now dimensionalized.
Tagging with a Typed Dimension
Some concepts have dimensions that require you to type a number for the dimension’s member. This is referred to as typed dimensions. You use typed dimensions when concept names include [grouping] or when using Further item concepts from balance Components headings.
To apply a typed dimension to a concept, click the fact. Then click the Manage Dimensionality tool in the XBRL Detail Tagging dialog box. The Available Members list appears below the date.
From the Available Members list, find and select the correct x-dimension axis for the concept. Then click the green Apply icon.
In the Enter value field, type the number for this dimension and press Enter. The number you type is based on the number of times you use the same typed dimension for the concept.
In this case, we have one typed dimension for Further item of tax increase (decrease) [component of adjusting items]. So we type 1 for the dimensions for both the current and previous year periods. If we used this same concept three times, we would type 1 for the first reported value, 2 for the second reported value, and so on.
After typing the number for the dimension, you have correctly tagged a fact with a typed dimension.