Queston on .innerHeight()

Queston on .innerHeight()

Could someone please explain the conflicting results that I have been getting with the JQuery function .innerHeight.  Documentation states "Gets the inner height (excluding the border and including the padding) for the first matched element"  That being said why does this code do the following display the .innerheight as 96?  Shouldn't it be 100 -2 = 98 + 5 = 103! 

<html> 
<head>     
<title>Testing InnerHeight</title>     
<script type="text/javascript" src="../jquery-1.8.3.js"></script>     
<style type="text/css">       
 p { 
         height: 100px;
          margin: 10px;   
          padding: 5px; 
          border: 2px solid #666;  
        }    
</style>     
<
script type="text/javascript">         
 $(function () {
         var p = $("p:first"); 
         $("p:last").text( "innerHeight:" + p.innerHeight() );             
  });     
</
script> 
</
head>
<body>     
<
p>.innerHeight should be (100px - 2px) + 5px = 103px  
 Yet .innerheight displays 96  
</p>       
<
p id="lastp"></p> 
</body> 
</html>

Thanks Dave.