diff --git a/Classes/Domain/Model/Document.php b/Classes/Domain/Model/Document.php
index 0361f3a..0246b00 100644
--- a/Classes/Domain/Model/Document.php
+++ b/Classes/Domain/Model/Document.php
@@ -29,19 +29,19 @@ class Document
     /**
      * The actual data to store to the document
      *
-     * @var array
+     * @var array|null
      */
     protected $data;
 
     /**
      * The version that has been assigned to this document.
      *
-     * @var int
+     * @var int|null
      */
     protected $version;
 
     /**
-     * @var string
+     * @var string|null
      */
     protected $id;
 
@@ -115,9 +115,9 @@ public function isDirty(): bool
     }
 
     /**
-     * @return int
+     * @return int|nulll
      */
-    public function getVersion(): int
+    public function getVersion(): ?int
     {
         return $this->version;
     }
@@ -144,9 +144,9 @@ public function setData(array $data): void
     }
 
     /**
-     * @return string
+     * @return string|null
      */
-    public function getId(): string
+    public function getId(): ?string
     {
         return $this->id;
     }
@@ -178,9 +178,9 @@ public function getType(): AbstractType
 
     /**
      * @param string $method
-     * @param string $path
+     * @param string|null $path
      * @param array $arguments
-     * @param string $content
+     * @param string|null $content
      * @return Response
      * @throws ElasticSearchException
      * @throws \Neos\Flow\Http\Exception
@@ -198,5 +198,4 @@ protected function setDirty(bool $dirty = true): void
     {
         $this->dirty = $dirty;
     }
-
 }
diff --git a/Tests/Functional/Domain/DocumentTest.php b/Tests/Functional/Domain/DocumentTest.php
index e25c34b..9a3d1fc 100644
--- a/Tests/Functional/Domain/DocumentTest.php
+++ b/Tests/Functional/Domain/DocumentTest.php
@@ -42,7 +42,7 @@ public function idOfFreshNewDocumentIsPopulatedAfterStoring(array $data = null)
         $document = new Document(new TwitterType($this->testingIndex), $data);
         static::assertNull($document->getId());
         $document->store();
-        static::assertRegExp('/\w+/', $document->getId());
+        static::assertMatchesRegularExpression('/\w+/', $document->getId());
     }
 
     /**