Often different items in a report have cross-references to each other. In a digital report these are usually links that can be clicked to navigate quickly between the items.
There are two aspects to the cross-referencing:
- Being able to see related content
- Specifically noting that one fact is related to another fact (perhaps it explains it or adds additional information to it)
Distinguishing the two above (somehow related versus related in a specific way) is part of this use-case.
Example
There is a note on Dues Receivable on page 7 of the filing which contains a link (“Bad debt”) back to the relevant table of figures:

Table with “Bad debt” figure:

Links
Inline Viewer – XBRL International Financial Statements June 30, 2020 and 2019
If you got to the Note 1 and section “Dues receivable”, you will see that “Bad debt” is a link to an item in the Cash flows table.