function collapseDiv(toggleId) {
  var body = document.getElementById(toggleId);
  if (!body) {
    return false;
  }
  body.style.display = 'none';
}

function closeAll() {
  var collection = document.getElementsByTagName('DIV');
  for (var cnt=0; cnt<collection.length; cnt++) {
    var el = collection[cnt];
    if (el.tagName == "DIV" && el.id != "" && el.className == "togglediv") {
      collapseDiv(el.id);
    }
  }
}

function toggleLayer( whichLayer ){  
  var elem, vis;  
  closeAll();
  if( document.getElementById ) // this is the way the standards work    
    elem = document.getElementById( whichLayer );  
  else if( document.all ) // this is the way old msie versions work      
    elem = document.all[whichLayer];  
  else if( document.layers ) // this is the way nn4 works    
    elem = document.layers[whichLayer];  
  vis = elem.style;  // if the style.display value is blank we try to figure it out here  
  if(vis.display==''&& 
     elem.offsetWidth!=undefined && 
     elem.offsetHeight!=undefined)    
     vis.display = (elem.offsetWidth != 0 && elem.offsetHeight != 0) ?'block' :'none';  
   vis.display = (vis.display==''||vis.display=='block') ?'none' :'block';
}