function showHide(id) {
	if (document.layers) {
		current = (document.layers[id].display == 'none') ? 'block' : 'none';
		document.layers[id].display = current;
	} else if (document.all) {
		current = (document.all[id].style.display == 'none') ? 'block' : 'none';
		document.all[id].style.display = current;
	} else if (document.getElementById) {
		vista = (document.getElementById(id).style.display == 'none') ? 'block' : 'none';
		document.getElementById(id).style.display = vista;
	}
}