var id=0;

function enableDropDown() {
  
  document.getElementById('contentNavMain').onmouseover = function() {
    document.getElementById('contentNavSubItems').style.display = 'block';
    clearTimeout(id);
  }

  document.getElementById('contentNavSubItems').onmouseover = function(){
    clearTimeout(id);
  }
  
  document.getElementById('contentNavMain').onmouseout = function(){
    id=setTimeout('hide()',800);
  }

  document.getElementById('contentNavSubItems').onmouseout = function(){
    id=setTimeout('hide()',800); 
    clearTimeout(id);
  }
}


function hide()
{
  document.getElementById('contentNavSubItems').style.display = 'none';
}