diff --git a/src/Provider/Dce/SystemDceSecurityProvider.php b/src/Provider/Dce/SystemDceSecurityProvider.php
index 6d6240b..7ff4076 100644
--- a/src/Provider/Dce/SystemDceSecurityProvider.php
+++ b/src/Provider/Dce/SystemDceSecurityProvider.php
@@ -229,6 +229,6 @@ class SystemDceSecurityProvider implements DceSecurityProviderInterface
             return '';
         }
 
-        return trim((string) substr($sid, $lastHyphen + 1));
+        return trim(substr($sid, $lastHyphen + 1));
     }
 }