function() {
            return Math.max(!Ext.isStrict ? document.body.scrollHeight : document.documentElement.scrollHeight, this.getViewportHeight());
        }
function() {
            return Math.max(!Ext.isStrict ? document.body.scrollHeight : document.documentElement.scrollHeight, this.getViewportHeight());
        }
function ( ) { return Math . max ( ! Ext . isStrict ? document . body . scrollHeight : document . documentElement . scrollHeight , this . getViewportHeight ( ) ) ; }
Retrieves the document height
@static
@return {Number} documentHeight
Retrieves the document height