Displaying of background information useful for interpretation

• In XBRL, background information to units can be given, question, how to display:
• If not considered, several observations may have the same values (duplicate dimension values), which does not conform to integrity constraint 12 [1].

• Example:

In XBRL

  <!--Unit Section-->
  <unit id="Unit14">
    <divide>
      <unitNumerator>
        <measure>iso4217:USD</measure>
      </unitNumerator>
      <unitDenominator>
        <measure>xbrli:shares</measure>
      </unitDenominator>
    </divide>
  </unit>
  <unit id="Unit13">
    <measure>xbrli:pure</measure>
  </unit>
  <unit id="Unit12">
    <measure>xbrli:shares</measure>
  </unit>
  <unit id="Unit1">
    <measure>iso4217:USD</measure>
  </unit>

...

  <us-gaap:CommonStockDividendsPerShareCashPaid contextRef="Duration_9_3_2007_To_8_31_2008" unitRef="Unit14" decimals="2">0.61</us-gaap:CommonStockDividendsPerShareCashPaid>
  <us-gaap:CommonStockDividendsPerShareCashPaid contextRef="Duration_9_1_2008_To_11_23_2008" unitRef="Unit13" decimals="3">0.160</us-gaap:CommonStockDividendsPerShareCashPaid>
  <us-gaap:CommonStockDividendsPerShareCashPaid contextRef="Duration_9_1_2008_To_8_30_2009" unitRef="Unit13" decimals="3">0.68</us-gaap:CommonStockDividendsPerShareCashPaid>
  <us-gaap:CommonStockDividendsPerShareCashPaid contextRef="Duration_9_1_2008_To_8_30_2009" unitRef="Unit14" decimals="2">0.68</us-gaap:CommonStockDividendsPerShareCashPaid>