Jquery Ajax多输入数据

Hi i want learn ajax but i have same problem. So i click (a11) button but my javascript alert 8, need to be 11. my other question i post data with ajax but say "no" thanks.!

<form action="" method="post" onclick="return false;" >
    <input type="text"  name="idh" value="'.$id.'"></input>
    <button id="my_button" class="my_button" name="my_button" data-value="'.$id.'">'.$baslik.$id.'</button>
    </form>

and my script

$('.my_button').click(function() {  
        var idm = $(this).attr('data-value');
        var idh = $("input[name=idh]").val();
            idh = $.trim(idh);
        //alert (id);
            $.ajax({
                type: "POST",
                url: "ajax.php",
                data: idm,
                success: function(cevapp){
                    alert (idh);
                }
            });
    });

my ajax.php