<script>
function my_f(objName, a) {
var object = document.getElementById(objName);
object.style.display = (object.style.display == 'none') ? '' : 'none'
a.innerHTML = (object.style.display == 'none') ? '(+)' : '(-)'
}
</script>
<a href="javascript:void(0)" onclick="my_f('textid', this)">(-)</a>
<div id="textid" style="display:block;">
скрытый текст
</div>