diff --git a/Classes/Domain/Factory/DocumentFactory.php b/Classes/Domain/Factory/DocumentFactory.php
index b9eaf1d..68fa51f 100644
--- a/Classes/Domain/Factory/DocumentFactory.php
+++ b/Classes/Domain/Factory/DocumentFactory.php
@@ -37,7 +37,7 @@ class DocumentFactory
      * @return Model\Document
      * @throws DocumentPropertiesMismatchException
      */
-    public function createFromResponse(Model\AbstractType $type, $id = null, Response $response)
+    public function createFromResponse(Model\AbstractType $type, $id, Response $response)
     {
         $content = $response->getTreatedContent();