/* function to expand/collapse a div */
function tierObject(objectid, imgid) {
	obj = document.getElementById(objectid);
	image = document.getElementById(imgid);
	if (obj)
		switchObject(obj);
	if(image) 
		switchImage(image,obj);	
	
}

function switchObject(obj) {
	if(obj.style.display == 'none') {
		obj.style.display = 'block';		
		return 'block';
	} else {
		obj.style.display = 'none';
		return 'none';
	}
}

function switchImage(image) {
	source = image.src;
	subb = source.substring(source.lastIndexOf('/') + 1, source.length);
	if(subb == 'plus.gif') 
		image.src = '/common/images/nav/minus.gif';	
	else
		image.src = '/common/images/nav/plus.gif';	
}