How to get custom line item's custom attribute's value after order complete
You can use the entity_metadata_wrapper on commerce_order

/**
 * Implements hook_commerce_checkout_complete
 */
function package_designer_commerce_checkout_complete($order) {

  $order_wrapper = entity_metadata_wrapper('commerce_order', $order);
  foreach ($order_wrapper-&gt;commerce_line_items as $line_item_wrapper) {
    if(isset($line_item_wrapper-&gt;field_package_configuration)){
      $package_configuration = $line_item_wrapper-&gt;field_package_configuration-&gt;value();  
      // You can also get the raw value like this:  
      // $package_configuration = $line_item_wrapper-&gt;field_package_configuration-&gt;raw();    
    }
  }

}