Bootstrap modal horizontal text overflowing

Bootstrap modal horizontal text overflowing

With a large text input inside <p> tags the text overflows the bounds of
the modal and off the screen requiring a horizontal scrollbar to read.
I've copied the example code from the Bootstrap documentation and simply
added a long text string inside the modal-body section. The example on the
Bootstrap documentation website seems to word wrap the text correctly but
my code does not.
Here is my markup:
<div class="modal fade in" id="myModal" tabindex="-1" role="dialog"
aria-labelledby="myModalLabel" aria-hidden="true">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal"
aria-hidden="true">&times;</button>
<h4 id="myModalLabel" class="modal-title">Modal Test</h4>
</div>
<div class="modal-body">
<p>Details below:</p>
<p>TEST:
aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa</p>
</div>
<div class="modal-footer">
<button type="button" class="btn btn-primary"
data-dismiss="modal">Done</button>
</div>
</div>
</div>
</div>
You can also see exactly what I mean by horizontal overflow on the
jsFiddle I created here: http://jsfiddle.net/pX39W/11/
I'm sure it's something simple and I've just been staring at it too long
to notice! Any help would be much appreciated.