diff --git a/lib/Drupal/config_translation/FormElement/DateFormat.php b/lib/Drupal/config_translation/FormElement/DateFormat.php
index 3cc9867..83cc2e0 100644
--- a/lib/Drupal/config_translation/FormElement/DateFormat.php
+++ b/lib/Drupal/config_translation/FormElement/DateFormat.php
@@ -22,10 +22,10 @@ class DateFormat extends Element {
    */
   public function getFormElement(array $definition, Language $language, $value) {
     if (class_exists('intlDateFormatter')) {
-      $description = $this->t('A user-defined date format. See the <a href="@url">PHP manual</a> for available options.', array('@url' => 'http://userguide.icu-project.org/formatparse/datetime'));
+      $description = $this->t('A user-defined date format. See the <a href="@url" target="_blank">PHP manual</a> for available options.', array('@url' => 'http://userguide.icu-project.org/formatparse/datetime'));
     }
     else {
-      $description = $this->t('A user-defined date format. See the <a href="@url">PHP manual</a> for available options.', array('@url' => 'http://php.net/manual/function.date.php'));
+      $description = $this->t('A user-defined date format. See the <a href="@url" target="_blank">PHP manual</a> for available options.', array('@url' => 'http://php.net/manual/function.date.php'));
     }
     $format = $this->t('Displayed as %date_format', array('%date_format' => \Drupal::service('date')->format(REQUEST_TIME, 'custom', $value)));
     return array(