Test

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.6/themes/smoothness/jquery-ui.css">
<iframe id="dialogFrame" src="about:blank" style="z-index: 1000; display: none; background: transparent;" frameborder="0" allowTransparency="true"></iframe>
<div id="dialogContainer"></div>

<div id="pdfContainer" style="position: relative; width: 100%; height: 700px;">
    <div style="position:absolute;z-index: 2;height: 100%; width: 100%">
        <object data="http://www.ccc.commnet.edu/faculty/sfreeman/cst%20250/jQueryNotes.pdf" type="application/pdf" style="width: 100%; height: 100%; z-index=1"></object>
    </div>
</div>

<script type="text/template" id="modalDialogTemplate">
    <link rel="stylesheet" href="//ajax.googleapis.com/ajax/libs/jqueryui/1.10.4/themes/smoothness/jquery-ui.css" />
    <div id="dialog" style="display:none; height:60%;" title="On Hold Reason" align="center">
        <br /><textarea id="messageTextBox" cols="32" rows="3" style="resize:none"></textarea>
        <div class="row" align="center"><br /></div><br />
    </div>
</script>

JavaScript

var showDialog = function() {

    // Determine the height and width of the dialog
    var height = $(window).height() * 0.55;
    var width = $(window).width() * 0.75;
    var paddedHeight = height + 20;
    var paddedWidth = width + 20;

    // Template
    var dialogTemplate = $("#modalDialogTemplate").html();
    var dialog = undefined;
    var dialogFrame = undefined;
    var resizable = true;
    var draggable = true;
    
    // Use a frame if IE < 10
    var agent = navigator.userAgent.toLowerCase();
    var useFrame = (agent.indexOf('msie') != -1 && parseFloat(agent.split('msie')[1]) < 10);
                  
    if(useFrame)
    {
        // If IE9 use an iframe
        dialogFrame = $("#dialogFrame").css({ 
            position: "absolute",
            background: "#efefef",
            width: paddedWidth + "px", 
            height: paddedHeight + "px", 
            top: "50%", 
            left: "50%",
            marginLeft: (-1 * (paddedWidth / 2)) + "px",
            marginTop: (-1 * (paddedHeight/ 2)) + "px",
            display: "block"
        });
        
        // Slight limitation of the frame
        resizable = false;
        draggable = false;
        
        // Insert the template into the frame
        var dialogFrameDoc = dialogFrame[0].contentWindow.document;
        dialogFrameDoc.open();
        dialogFrameDoc.write(dialogTemplate);
        dialogFrameDoc.close();
    
        dialog = dialogFrame.contents().find("#dialog");
    } else {
        // Use the dialog container
        dialog = $("#dialogContainer").html(dialogTemplate).find("#dialog");
    }
    
    // Close action
    var close = function() {
        // Close the dialog
        dialog.dialog("close");
        dialogFrame.remove();
    };
    
    dialog.dialog({
        autoOpen: true,
        draggable: resizable,
        resizable: draggable,
        title: 'Dialog',
        modal: true,
        stack: true,
        height: height,
        width: width,
       ...