没有从php中的tinyme获取post值

i am new to this tinymce editor. I have used it on my site but i am facing a little problem that is, when i add a class to the textarea my content does not update, means i do not get values by $_POST. but when i remove the editor class from the textarea i get the values and content is updated.. below is my code please help what to do ??

<script type="text/javascript" src="javascript/tinymce/tiny_mce.js?1"></script>
<textarea  id="wysiwyg"   name="longDescription" style="padding: 0; width: 100%; height: 250px;" placeholder="Type a description for this product here..."><?php echo $editdetails;?></textarea>
if( $_POST['update']){
$details= mysql_real_escape_string( strip_tags( $_POST["longDescription"] ) ) ;
//update query//
}

how to get the post value ?? in the $details variable ?? as i am getting value without using the id="wysiwyg"

Found the solution

i just removed mysql_real_escape_string( strip_tags()) from

mysql_real_escape_string( strip_tags( $_POST["longDescription"] ) ) ;