Sometimes you may need to reuse the same data in several sections of your document and the data requires different XBRL tagging. You can maintain this data from a single source with two separate links and avoid XBRL issues through a process called Chain Linking.
When to Chain Link
The first sign that a chain link may be necessary is that a number is disclosed with different levels of detail throughout the document. For example, you may have the Net Income (Loss) Attributable to Parent concept in the Income Statement in the amount of $5,252 and also disclose this value in your Statement of Stockholders’ Equity, noting that the value is considered part of “Retained Earnings.” Although these represent the same amounts, the tagging must be different so that the Statement of Stockholders’ Equity appropriately reports that net income is a part of the retained earnings component of equity, whereas the Income Statement will not be as specific. In the images below, an Axis and Member have been applied where they should not be.
Statement of Stockholders’ Equity:
Removing the Axis and Member from the Income Statement would fix this incorrect tagging as well as correct the calculation relationship. However, when you remove the Axis/Member from the values they will be removed in all locations that share that same linking. In the Link Properties panel, you can see that the source value for Net Income (Loss) Attributable to Parent in the workbook has been used to create destination links in both the Consolidated Statements of Earnings and Stockholders’ Equity disclosure.
Establishing Chain Linking
In this example, you would set up your chain linking as follows:
In the P&L section of the workbook, verify that the Net Income (Loss) Attributable to Parent values are correct (Cell C32 in the image below). This will become the single source where you will update these numbers in the future.
In this workbook section, create a new column and label the new column "Chain Linking."
3. Now go to the newly created column (columns D above) and insert a formula to pull the newly pasted value over by reference. E.g., in cell D32 type the formula =C32.
4. Link the numbers in cells D32 to your document. You can link over the existing links.
5. This relinking process will disconnect your XBRL tag. In order to re-establish the link, turn XBRL off and then back on in order to get the Disconnected XBRL Data message to appear. Share your XBRL when prompted.
6. Click Copy XBRL in the Disconnected Data box and then paste onto the corresponding number that you just finished relinking.
7. Finally, use the Add/Re-Add to XBRL Outline option in the XBRL Detail Tagging Window to reassociate the tag with the appropriate XBRL outline section.
Removing the Axis/Member
Now that you have verified that the chain link has been properly established, you can remove the Axis/Member from the Net Income (Loss) Attributable to Parent concept in the Income Statement. This should not impact the XBRL tags applied to values in the Statement of Stockholders’ Equity section.