var vTimer;
var vId;

function Show (Id)
{
	if (vId)
		document.getElementById (vId).style.visibility = 'hidden';
	document.getElementById (Id).style.visibility = 'visible';
	clearTimeout (vTimer);
}

function Hide (Id)
{
	document.getElementById (vId = Id).style.visibility = 'visible';
	vTimer = setTimeout ("document.getElementById (vId).style.visibility = 'hidden'", 500);
}