window.onload = function () {
   if (( window.innerWidth || (window.document.documentElement.clientWidth || window.document.body.clientWidth ) ) > 950) {
        document.getElementById("IspTable").width = "950px";
   } else {
        document.getElementById("IspTable").width = "100%";
   } 
}

window.onresize = function (evt) {
   if (( window.innerWidth || (window.document.documentElement.clientWidth || window.document.body.clientWidth ) ) > 950) {
        document.getElementById("IspTable").width = "950px";
   } else {
        document.getElementById("IspTable").width = "100%";
   } 
}