var curSub = null;

function showMenu(_id){
	var prevSub = curSub;
	var subMenu = _id + '-submenu';
	curMenu = document.getElementById(_id);
	curSub = document.getElementById(subMenu);
	
	if (prevSub != null && prevSub != undefined && prevSub != curSub){
		prevSub.style.visibility = 'hidden';
		prevSub.style.display = 'none';
	} 
	
	if (curSub != null){
		curSub.style.left = curMenu.offsetLeft-30+ 'px';
		curSub.style.visibility = 'visible';
		curSub.style.display = 'block';
	}
}

function hideMenu(){
	try{
		curSub.style.visibility = 'hidden';
		curSub.style.display = 'block';
	}
	catch(err){
	}
}