var cur_lyr;	// holds id of currently visible layer
function swapLayers(id) {
  if (cur_lyr) hideLayer(cur_lyr);
  showLayer(id);
  cur_lyr = id;
}

function showLayer(id) {
  var lyr = getElemRefs(id);
  if (lyr && lyr.css) lyr.css.visibility = "visible";
}


function hideLayer(id) {
  var lyr = getElemRefs(id);
  if (lyr && lyr.css) lyr.css.visibility = "hidden";
}

function toggleLayer_vis(id) {
	var lyr = getElemRefs(id);
	if( lyr && lyr.css ) {
		if( lyr.css.visibility == "visible" ) { lyr.css.visibility = "hidden"; }
		else { lyr.css.visibility = "visible"; }
	}
}

function showItem(id) {
  var lyr = getElemRefs(id);
	var browserName=navigator.appName;
	if (browserName=="Microsoft Internet Explorer")
	{
	  if (lyr && lyr.css) lyr.css.display = "block";
	}
	else
	{
	  if (lyr && lyr.css) lyr.css.display = "table";
	}
}


function toggleLayer_display(id, model) {
	if( model == null ) { model = "block"; }
	var lyr = getElemRefs(id);
	if( lyr && lyr.css ) {
		if( lyr.css.display == model ) { lyr.css.display = "none"; }
		else { lyr.css.display = model; }
	}
}


function getElemRefs(id) {
	var el = (document.getElementById)? document.getElementById(id): (document.all)? document.all[id]: (document.layers)? document.layers[id]: null;
	if (el) el.css = (el.style)? el.style: el;
	return el;
}