function showLightboxOverlay()
{
	var overlay = document.getElementById("lightboxOverlay");
	var create = false;

	if(!overlay)
	{
		create = true;
		var overlay = document.createElement("DIV");
		overlay.id= "lightboxOverlay";
	}
	else
	{
		overlay.style.display = "block";
	}

	overlay.style.height = document.documentElement.scrollHeight + "px";

	if(create)
	{
		document.body.appendChild(overlay);
	}
}


function hideLightboxOverlay()
{
	var overlay = document.getElementById("lightboxOverlay");

	if(overlay)
	{
		overlay.style.display = "none";
	}
}