function openCloseDiv(this_navID, this_level){
	the_div = document.getElementById('div_' + this_navID);
	plus_minus_img = document.getElementById('pmIMG_' + this_navID);	
	if (the_div){
		if (the_div.style.display == 'block') {
			the_div.style.display  = 'none';
			plus_minus_img.src = plus_minus_img.src.replace('minus','plus');
			plus_minus_img.title = 'Expand';	
		}else{
			the_div.style.display  = 'block';
			plus_minus_img.src = plus_minus_img.src.replace('plus','minus');	
			plus_minus_img.title = 'Collapse';	
		}
	}
}