function ShowHide(id) 
{
  var itm = null;
  if (document.getElementById) {
	itm = document.getElementById(id);
  } else if (document.all){
	itm = document.all[id];
  } else if (document.layers){
	itm = document.layers[id];
  }

  if (!itm) {
   // do nothing
  }
  else if (itm.style) {
	if (itm.style.display == "none") {
	  itm.style.display = "";
	}
	else {
	  itm.style.display = "none";
	}
  }
  else {
	itm.visibility = "show";
  }
}