function toggleTable (prefix)
{
  var arrowEl = document.getElementById(prefix + "-arrow");
  var tableEl = document.getElementById(prefix + "-table");

  if (tableEl.style.display != 'none')
    closeTable(arrowEl, tableEl);
  else
    openTable(arrowEl, tableEl);

  return false;
}

function openTable(arrow, table)
{
  arrow.innerHTML = "►"; // unicode for right arrow
  table.style.display = '';
 
  return false;
}

function closeTable(arrow, table)
{
  arrow.innerHTML = "▼"; // unicode down arrow
  table.style.display = 'none';
 
  return false;
}

function initializeToggle (elAr)
{
  for ( var i = 0; i < elAr.length; i++)
  {
    var arrowEl = document.getElementById(elAr[i] + "-arrow");
    var tableEl = document.getElementById(elAr[i] + "-table");

    closeTable(arrowEl, tableEl);
  }
  return false;
}