Reveal Content With Checkbox In Form

I have a form which check boxes. The last check box is labeled "other". What I want is that when the user clicks other my text field contained in my hidden "details" div will be displayed so they can specify "other".

Here is the JS code I have in the head of my page:
<script type="text/javascript" language="JavaScript"><!--
function RemoveContent(d) {
document.getElementById(d).style.display = "none";
}function InsertContent(d) {
document.getElementById(d).style.display = "";
}
//--></script>

Here is the code on the "other" check box:
<label class="checks">
<input type="checkbox" name="Other" id="other"
onselect="PresentForm ('details');" />
Other</label>

And the code for the details div:
<div id="details" class="checks">
<label >
<input type="text" name"details" size="30" />Please Explain</label>
</div>

Here is the CSS for the details text field:
#details {
padding-left:20px;
display:none;
}