function toggle_det(elementname)
{
 if (document.getElementById(elementname).style.visibility == "visible" )
 {
     document.getElementById(elementname).style.visibility = "hidden";
     document.getElementById(elementname).style.position = "absolute";
 } else {
     document.getElementById(elementname).style.visibility = "visible";
     document.getElementById(elementname).style.position = "relative";
 };
}