function visibilite(obj, thingId)
{
    var contenu = document.getElementById("div"+thingId);
    if (contenu.style.display == "none")
    {
        contenu.style.display = "";
        obj.className = "icon_moins";	
    } else {
        contenu.style.display = "none";
        obj.className = "icon_plus";
    }
	hauteur();
}