function foldingFunc(id)
{
	var el = document.getElementById(id);
	if (el.style.display=="block"){
		el.style.display = 'none';
		document.images[id + '_foldingImg'].src = "http://image.alibaba.co.jp/images/menuul_close.gif";
	}else {
		el.style.display = 'block';
		document.images[id + '_foldingImg'].src = "http://image.alibaba.co.jp/images/menuul_open.gif";
	}
}