Edit in JSFiddle

var updateInfo = function(dd, pdd) {
var a = document.getElementById('a');
var result = '';
var log = function(msg) {
    result += msg + '<br/>';
}
log('local: ' + dd);
log('parent: ' + pdd);
a.innerHTML = result;
}
var i = setInterval(function() {
        var dd1 = "error", dd2 = "error";
        try{dd1 = document.domain;}catch(e){}
        try{dd2 = parent.document.domain;}catch(e){
            clearInterval(i);
        }
        updateInfo(dd1, dd2);    
}, 100);

<div id=a></div>

#a {
    display: block;
    background: lightblue;
    width: 300px;
    height: 130px;
}
body{
    margin:0px;
    padding:0px;
}