function toggle(div_id, otherwindow) {
	var el = document.getElementById(div_id);
        var oel = document.getElementById(otherwindow);

	if ( el.style.display == 'none' ) {	el.style.display = 'block';}
	else {el.style.display = 'none';}

        if (el != oel)
        {
          if (oel.style.display == 'block')
             {oel.style.display = 'none';}
        }
}
function blanket_size(popUpDivVar) {
	if (typeof window.innerWidth != 'undefined') {
		viewportheight = window.innerHeight;
	} else {
		viewportheight = document.documentElement.clientHeight;
	}
	if ((viewportheight > document.body.parentNode.scrollHeight) && (viewportheight > document.body.parentNode.clientHeight)) {
		blanket_height = viewportheight;
	} else {
		if (document.body.parentNode.clientHeight > document.body.parentNode.scrollHeight) {
			blanket_height = document.body.parentNode.clientHeight;
		} else {
			blanket_height = document.body.parentNode.scrollHeight;
		}
	}
	var blanket = document.getElementById('blanket');

	blanket.style.height = (blanket_height - 30) + 'px' ;
        
	var popUpDiv = document.getElementById(popUpDivVar);
	popUpDiv_height=blanket_height/2-150;//150 is half popup's height
	popUpDiv.style.top = popUpDiv_height + 'px';
}
function window_pos(popUpDivVar, pos_top, pos_left) {
	if (typeof window.innerWidth != 'undefined') {
		viewportwidth = window.innerHeight;
	} else {
		viewportwidth = document.documentElement.clientHeight;
	}
	if ((viewportwidth > document.body.parentNode.scrollWidth) && (viewportwidth > document.body.parentNode.clientWidth)) {
		window_width = viewportwidth;
	} else {
		if (document.body.parentNode.clientWidth > document.body.parentNode.scrollWidth) {
			window_width = document.body.parentNode.clientWidth;
		} else {
			window_width = document.body.parentNode.scrollWidth;
		}
	}
	var popUpDiv = document.getElementById(popUpDivVar);
	window_width=window_width/2-150;//150 is half popup's width
	popUpDiv.style.left = pos_left + 'px';
        popUpDiv.style.top  = pos_top  + 'px';
}
function popup(windowname, otherwindow, pos_top, pos_left) {
	blanket_size(windowname);
	window_pos(windowname, pos_top, pos_left);
	toggle('blanket', otherwindow);
	toggle(windowname, otherwindow);		
}