XBRL Instance Documents

An instance document is a collection of facts that together make up a business report. It is the "filled-in form" that references an XBRL taxonomy for its vocabulary.

Structure

An instance document is an XML document with root element <xbrli:xbrl>:

<xbrli:xbrl xmlns:xbrli="http://www.xbrl.org/2003/instance"
            xmlns:us-gaap="http://fasb.org/us-gaap/2024"
            xmlns:iso4217="http://www.xbrl.org/2003/iso4217">

  <!-- 1. Schema references (links to taxonomy) -->
  <link:schemaRef xlink:href="taxonomy.xsd" xlink:type="simple"/>

  <!-- 2. Context definitions -->
  <xbrli:context id="FY2024">
    <xbrli:entity>
      <xbrli:identifier scheme="http://www.cipc.co.za">2024/123456/07</xbrli:identifier>
    </xbrli:entity>
    <xbrli:period>
      <xbrli:startDate>2024-01-01</xbrli:startDate>
      <xbrli:endDate>2024-12-31</xbrli:endDate>
    </xbrli:period>
  </xbrli:context>

  <!-- 3. Unit definitions -->
  <xbrli:unit id="ZAR">
    <xbrli:measure>iso4217:ZAR</xbrli:measure>
  </xbrli:unit>

  <!-- 4. Facts -->
  <us-gaap:Revenue contextRef="FY2024" unitRef="ZAR" decimals="-3">
    5000000
  </us-gaap:Revenue>

</xbrli:xbrl>

The Four Parts

1. Schema References

Link the instance to its taxonomy -- this is what triggers the DTS discovery process.

2. Contexts

Define who (entity), when (period), and optionally additional qualifiers like dimensional breakdowns.

3. Units

Define measurement units for numeric facts (currencies, shares, pure numbers).

4. Facts

The actual reported data. Each fact is an XML element referencing:

• A concept (the element name from the taxonomy)
• A context (via contextRef)
• A unit (via unitRef, for numeric facts)
• Accuracy: decimals or precision attribute

Types of Facts

Type	Description	Example
Item	Single value	Revenue = R5,000,000
Tuple	Group of related values	(Deprecated in [[15 Open Information Model

Accuracy: Decimals vs Precision

For numeric facts, you must specify accuracy:

• decimals="-3" means accurate to the nearest thousand (R5,000,000 could be R4,999,500 to R5,000,499)
• decimals="0" means accurate to the nearest whole unit
• decimals="2" means accurate to two decimal places
• decimals="INF" means exact value

Footnotes

Optional explanatory text linked to specific facts:

<link:footnoteLink>
  <link:loc xlink:href="#fact1" xlink:label="factLoc"/>
  <link:footnote xlink:label="fn1" xml:lang="en">
    Revenue includes R500,000 from discontinued operations.
  </link:footnote>
  <link:footnoteArc xlink:from="factLoc" xlink:to="fn1"
    xlink:arcrole="http://www.xbrl.org/2003/arcrole/fact-footnote"/>
</link:footnoteLink>

Instance vs Inline XBRL

Traditional instance documents are pure XML -- not human-readable. 13 Inline XBRL solves this by embedding the same tags directly into HTML documents that humans can read in a browser.