function showLargeImg(control) {

    var doc = window.document.getElementById("medtravelroot");
    var body = document.getElementById("medtravelbody");
    var cover = document.getElementById("coverDiv");
    var coverImg = document.getElementById("coverImgObject");

    var chromeScroll = document.body.scrollTop.toString() + "px";
    var mozScroll = document.documentElement.scrollTop.toString() + "px";
    
    var src = control.src;
    src = src.replace("/thumbs", "");
    coverImg.src = src;

    cover.style.display = "block";
    doc.style.overflow = "hidden";
    body.style.overflow = "hidden";

    if (chromeScroll == "0px" && mozScroll != "0px") {
        cover.style.top = mozScroll;
    }
    else if (chromeScroll != "0px" && mozScroll == "0px") {
        cover.style.top = chromeScroll;
    }
    else if (chromeScroll == "0px" && mozScroll == "0px") {
        cover.style.top = mozScroll;
    }
    else if (chromeScroll != "0px" && mozScroll != "0px") {
        cover.style.top = mozScroll;
    }
}

function removeCover() {

    var doc = window.document.getElementById("medtravelroot");
    var body = document.getElementById("medtravelbody");
    var cover = document.getElementById("coverDiv");
    var coverImg = document.getElementById("coverImgObject");

    cover.style.display = "none";
    doc.style.overflow = "auto";
    body.style.overflow = "auto";

    coverImg.src = "";
}