IDEA does not certify. They are a professional association. This site will give you information about a variety of organizations that certify in a variety of fitness fields. It looks from your question as though you have tagged FITOUR… I would suggest the best way to ask them about their water certifications is to go to their web site and look for a contact section.
If you want to see other groups that offer certifications this is a link to the IDEA tool that lets you compare various certifications. I marked it to the spot for Aqua certs.