title: document.getElementById(...).style.display is blank
body: <pre><code>function test( id )
  {
      alert( document.getElementById( id ).style.display );
  }
  </code></pre>
  
  <p>What exactly does getElementById.style.display return? Is it an object, or a value? The alert shows nothing at all. I'm not using pure numbers for the id and it is unique.</p>