var timeout	= 500;
var closetimer	= 0;
var ddmenuitem	= 0;

function menuopen(id) {	

	menucancelclosetime();

	if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';

	ddmenuitem = document.getElementById(id);
	ddmenuitem.style.visibility = 'visible';

}

function menuclose() {
	if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';
}

function menuclosetime()
{
	closetimer = window.setTimeout(menuclose, timeout);
}

function menucancelclosetime() {
	if(closetimer)
	{
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}

document.onclick = menuclose;