function showLevel( _divId ) {
        var thisLevel = document.getElementById( _divId );
        if ( thisLevel.style.display == "none") {
                thisLevel.style.display = "block";
                }
        else {
                hideLevel( _divId);
                }
        }
function hideLevel( _divId) {
        var thisLevel = document.getElementById( _divId );
        thisLevel.style.display = "none";
        }