var old = "";
function show_sublevel(what) {
	if (document.getElementById(what).style.visibility == "visible") document.getElementById(what).style.visibility = "hidden";
	else {
		if (old != "") document.getElementById(old).style.visibility = "hidden";
		old = what;
		document.getElementById(what).style.visibility = "visible";
	}
}

function hideElement(id){
  if(document.getElementById(id).style.display != "none"){
    document.getElementById(id).style.display="none";
  }
}

function showElement(id){
  if(document.getElementById(id).style.display != "block"){
    document.getElementById(id).style.display="block";
  }
}

function bar(url)
{
  wasOpen  = false;
  win = window.open(url);    
  return (typeof(win)=='object')?true:false;
}