function showMooringOpts()
{
    return showHide('mooringopts', 'MooringBerthType', '0');
}

function showHide(sDiv, sSelect, sOff)
{
    var oDiv = document.getElementById(sDiv);
    var oSelect = document.getElementById(sSelect);
    var sValue = oSelect.value;
    oDiv.style.display = ( sValue == sOff ) ? 'none' : 'block';
}