function show(id){
	if(document.getElementById(id)){
		e = document.getElementById(id);
		e.style.visibility = "visible";
		e.style.display = "block";
	}
	
}

function hide(id){
	if(document.getElementById(id)){
		e = document.getElementById(id);
		e.style.visibility = "hidden";
		e.style.display = "none";
	}
	
}

// hides if element is shown, shows, if element is hidden
function showHide(id){
	if(document.getElementById(id)){
		e = document.getElementById(id);
		if(e.style.display=='none'){
			show(id);
		}
		else{
			hide(id);
		}
	}
}