function show ($element) {
  document.getElementById($element).style.display = 'block';
}

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

function showhide ($element) {
  if (document.getElementById($element).style.display == 'block') {
	  document.getElementById($element).style.display = 'none';
	} else {
	  document.getElementById($element).style.display = 'block';
	}
}