function show(id_1, id_2) {
	var id_1;
	var id_2;
	
	if (document.getElementById(id_1)) {
		document.getElementById(id_1).style.display = "block";
	}
	if (document.getElementById(id_2)) {
		document.getElementById(id_2).style.display = "block";
	}
}

function hide(id_1, id_2) {
	var id_1;
	var id_2;
	
	if (document.getElementById(id_1)) {
		document.getElementById(id_1).style.display = "none";
	}
	if (document.getElementById(id_2)) {
		document.getElementById(id_2).style.display = "none";
	}
}