var timeout = 500;
var closetimer = 0;
var ddmenuitem = 0;

function ddmopen(id) {	
  ddmcancelclose();
  if(ddmenuitem)
    ddmenuitem.style.visibility = 'hidden';
  ddmenuitem = document.getElementById(id);
  ddmenuitem.style.visibility = 'visible';
}

function ddmclose() {
  if(ddmenuitem)
    ddmenuitem.style.visibility = 'hidden';
}

function ddmclosetime() {
  closetimer = window.setTimeout(ddmclose, timeout);
}

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

document.onclick = ddmclose;