XBRL International has produced a number of case studies to describe how important organisations have made use of XBRL.  These studies explain the background to each XBRL project, the reasons for adopting XBRL, the main steps involved, key results, lessons learned and next steps.  They should be of interest to all those concerned with the practical use of XBRL.

Here is the list of available case studies at this moment:

• The National Bank of Belgium
• The Bank of Japan
• The Bank of Spain
• The Tokyo Stock Exchange
• The FFIEC and US Banking Regulation

You can read it  here.