How to define document height is changed in javascript/jquery?

I have a problem for showing a full size div over all of my HTML document. I've set the size of my div to my page开发者_如何学C width and height. and write this codes for resizing of document:

$(window).resize(function(){
    sysSetOverlaySize(cDivOverlay);//cDivOverlay is my full size div
});

when my browser window resize this function is called and set the new size of my div from the size of my page. but when tinymce increase my page height this function only called in FF. I want some action to define when document height is changed. Thanks a lot

How about doing it in css with positioning:

#myDiv {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
}