var contentBoxId="content";
var contentFrameHeight=330;
function showHideScrollArrows(){
	contentIframe=window.parent.frames['content-frame'];
	contentBox=document.getElementById(contentBoxId);
	if(contentBox) {
		contentBoxHeight = (contentBox.offsetHeight > contentBox.scrollHeight) ? contentBox.offsetHeight : contentBox.scrollHeight + 30;

		//hide scroll arrows if not needed
		if (contentBoxHeight < contentFrameHeight){
			window.parent.document.getElementById("scroll_up").style.visibility="hidden";
			window.parent.document.getElementById("scroll_down").style.visibility="hidden";
		} else{
			window.parent.document.getElementById("scroll_up").style.visibility="visible";
			window.parent.document.getElementById("scroll_down").style.visibility="visible";
		}
	}
}