function toggleLayer(whichLayer){
	if (document.getElementById){
		// Modern
		var style2 = document.getElementById(whichLayer).style;
		style2.display = style2.display? "":"block";
		document.getElementById(whichLayer).innerHTML = "<center><ifr"+"ame src='/pages/filter.aspx' style='width:700px' frameborder=no scrolling=no></ifr"+"ame></center>";
	}
	else if (document.all){
		// Old IE
		var style2 = document.all[whichLayer].style;
		style2.display = style2.display? "":"block";
	}
	else if (document.layers){
		// NN4
		var style2 = document.layers[whichLayer].style;
		style2.display = style2.display? "":"block";
	}
}