public static function isId($id) {
	  // check passed data
    if(!is_string($id)) {
	    // bad data passed
	    throw new LinkedInException('LinkedIn->isId(): bad data passed, $id must be of type string.');
	  }
	  
	  $pattern = '/^[a-z0-9_\-]{10}$/i';
	  if($match = preg_match($pattern, $id)) {
	    // we have a match
	    $return_data = TRUE;
	  } else {
	    // no match
	    $return_data = FALSE;
	  }
	  return $return_data;
	}