var activeMenuId = null;
var realHide = false;
var hideTimeout = 1000;

function showSub(id){
	if(id != activeMenuId){
		realHideSub();
	}
	realHide = false;
	var d = document.getElementById('sub_' + id);
	if(!d){
		return;
	}
	d.style.display = 'block';
	activeMenuId = id;
}

function hideSub(){
	setTimeout('realHideSub()', hideTimeout);
	realHide = true;
	/*
	var d = document.getElementById('sub_' + activeMenuId);
	if(!d){
		return;
	}
	activeMenuId = null;
	d.style.display = 'none';
	*/
}

function realHideSub(){
	if(!realHide){
		return;
	}
	var d = document.getElementById('sub_' + activeMenuId);
	if(!d){
		return;
	}
	activeMenuId = null;
	d.style.display = 'none';
}