XY detecting mouse value

HTML

<script src="http://www.amcharts.com/lib/3/amcharts.js"></script>
<script src="http://www.amcharts.com/lib/3/xy.js"></script>
<div id="chartdiv" style="width: 100%; height: 362px;"></div>
<div id="values"></div>

JavaScript

var chart;
var xAxis;
var yAxis;

var chartData = [
    {
        "y": 10,
        "x": 14,
        "value": 59,
        "y2": -5,
        "x2": -3,
        "value2": 44
    },
    {
        "y": 5,
        "x": 3,
        "value": 50,
        "y2": -15,
        "x2": -8,
        "value2": 12
    },
    {
        "y": -10,
        "x": -3,
        "value": 19,
        "y2": -4,
        "x2": 6,
        "value2": 35
    },
    {
        "y": -6,
        "x": 5,
        "value": 65,
        "y2": -5,
        "x2": -6,
        "value2": 168
    },
    {
        "y": 15,
        "x": -4,
        "value": 92,
        "y2": -10,
        "x2": -8,
        "value2": 102
    },
    {
        "y": 13,
        "x": 1,
        "value": 8,
        "y2": -2,
        "x2": -3,
        "value2": 41
    },
    {
        "y": 1,
        "x": 6,
        "value": 35,
        "y2": 0,
        "x2": -3,
        "value2": 16
    }
];

AmCharts.ready(function () {
    // XY Chart
    chart = new AmCharts.AmXYChart();
    chart.pathToImages = "http://www.amcharts.com/lib/3/images/";
    chart.dataProvider = chartData;
    chart.startDuration = 1.5;
    
    // AXES
    // X
    xAxis = new AmCharts.ValueAxis();
    xAxis.position = "bottom";
    xAxis.axisAlpha = 0;
    xAxis.minMaxMultiplayer = 1.2;
    xAxis.autoGridCount = true;
    chart.addValueAxis(xAxis);
    
    // Y
    yAxis = new AmCharts.ValueAxis();
    yAxis.position = "top";
    yAxis.minMaxMultiplier = 1.2;
    yAxis.axisAlpha = 0;
    yAxis.autoGridCount = true;
    chart.addValueAxis(yAxis);
    
    // GRAPHS
    // first graph
    var graph = new AmCharts.AmGraph();
    graph.valueField = "value";
    graph.lineColor = "#b0de09";
    graph.xField = "x";
    graph.yField = "y";
    graph.lineAlpha = 0;
    graph.bullet = "bubble";
    graph.balloonText = "x:<b>[[x]]</b> y:<b>[[y]]</b><br>value:<b>[[value]]</b>"
    chart.addGraph(graph);
    
    // second graph
    graph = new AmCharts.AmGraph();
    graph.valueField...