/* Formatting function for row details */
function fnFormatDetails(oTable, nTr) {
    var aData = oTable.fnGetData(nTr);
    var sOut = '<table cellpadding="5" cellspacing="0" border="0" style="padding-left:50px;">';
    sOut += '<tr><td>Rendering engine:</td><td>' + aData[1] + ' ' + aData[4] + '</td></tr>';
    sOut += '<tr><td>Link to source:</td><td>Could provide a link here</td></tr>';
    sOut += '<tr><td>Extra info:</td><td>And any further details here (images etc)</td></tr>';
    sOut += '</table>';

    return sOut;
}

/* Formating function for row details */
function fnFormatDetails(oTable, nTr) {
    var aData = oTable.fnGetData(nTr);
    var sOut = 'ajax/order_history_orderlines.asp?orderid=' + aData[1];

    return sOut;
}

$.ajax({
  url: 'ajax/order_history_orderlines.asp?orderid=' + aData[1],
  success: function(data) {
  /* do something with your data here */
  }
});