function changeVisibility(idDiv){
	var elem = document.getElementById(idDiv);
	if(elem.style.visibility == 'hidden'){
		elem.style.visibility = 'visible';
		elem.style.display = 'block';
	}
	else{
		elem.style.visibility = 'hidden';
		elem.style.display = 'none';
	}
}
/*
function valida(formName){
	var form = document.getElementById(formName);
	var i;
	var aprovado = 1;
	
	for(i = 0;i < form.elements.length; i++){
		if(form.elements[i].getAttribute('required') != "false" && form.elements[i].getAttribute('required') != false){
			if(form.elements[i].value == "" || form.elements[i].value == null){			
				aprovado = 0;
				break;
			}
		}
	}
	
	if(aprovado == 0){
		alert("Please fill all required fields");
		return false;
	}
	else{
		return true;
	}
	
}*/