var timeout	= 500;
var closetimer	= 0;
var menu = 0;

function mopen(id)
{	
    cancel();
    if(menu) menu.style.visibility = 'hidden';
    menu = document.getElementById(id);
    menu.style.visibility = 'visible';

}
function mclose()
{
	if(menu) menu.style.visibility = 'hidden';
}

function mclosetime()
{
	closetimer = window.setTimeout(mclose, timeout);
}

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

document.onclick = mclose;