docs: function (tagName) {
  
              // A pointer to the style might be already there or an element with the correct id might be there
              var tag = this.__styleTagPool[tagName];
  
              if (!tag) {
                  var id = this.__TAG_PREFX + tagName;
                  tag = ariaUtilsDom.getElementById(id);
  
                  if (!tag) {
                      // If missing, create one
                      var document = Aria.$window.document;
                      var head = document.getElementsByTagName("head")[0];
                      tag = document.createElement("style");
  
                      tag.id = id;
                      tag.type = "text/css";
                      tag.media = "all"; // needed as the default media is screen in FF but all in IE
  
                      head.appendChild(tag);
                      tag = head.lastChild;
                  }
  
                  this.__styleTagPool[tagName] = tag;
              }
              return tag;
          }