var toperiod = 1000;
var currMenu = null;
var toid = null;
function showD(menuId)
{
    var menu = document.getElementById('menu_' + menuId);
    menu.style.display='';
    if (currMenu == menu && toid != null)
    {
       clearTimeout(toid);
       toid = null;
    }
    else if (currMenu != menu)
    {
       if (toid != null)
       {
	        clearTimeout(toid);
            toid = null;
        }
       sh();
    }
    currMenu = menu;
    return;
}
function hideD(menuId)
{
    var menu = document.getElementById('menu_' + menuId);
    if (toid != null && menu == currMenu)
       clearTimeout(toid);
 	toid = setTimeout('sh()',toperiod); 
    return;
}
function sh()
{
    if (currMenu != null)
    {
    	currMenu.style.display = 'none';
    	currMenu = null;
    }
}