diff --git a/Bundle/CoreBundle/src/Ckeditor/CkeditorConfiguration.php b/Bundle/CoreBundle/src/Ckeditor/CkeditorConfiguration.php
index 7b1b5db..b16b57c 100644
--- a/Bundle/CoreBundle/src/Ckeditor/CkeditorConfiguration.php
+++ b/Bundle/CoreBundle/src/Ckeditor/CkeditorConfiguration.php
@@ -58,6 +58,10 @@ private function resolveConfig(array $bundleConfig)
         $this->configs['full'] = self::FULL_CONFIG;
 
         foreach ($bundleConfig['configs'] as $configName => $config) {
+            if (!is_array($config)) {
+                throw new \RuntimeException(sprintf('[Ckeditor] Invalid "umbrella_core.configs.%s" config. Ckeditor config must be an array of options. ', $configName));
+            }
+
             $this->configs[$configName] = $config;
         }
 
diff --git a/Bundle/CoreBundle/src/DependencyInjection/Configuration.php b/Bundle/CoreBundle/src/DependencyInjection/Configuration.php
index b3e2305..74d029b 100644
--- a/Bundle/CoreBundle/src/DependencyInjection/Configuration.php
+++ b/Bundle/CoreBundle/src/DependencyInjection/Configuration.php
@@ -63,15 +63,14 @@ private function ckeditorSection(ArrayNodeDefinition $rootNode)
                     ->end()
                 ->scalarNode('default_config')
                     ->defaultValue('full')
-                    ->info('Default config to use on CkeditorType (if none specified).')
+                    ->info('Default config to use on CkeditorType (if none specified on CkeditorType).')
                     ->end()
                 ->arrayNode('configs')
                     ->info('List of configs for CkeditorType @see Umbrella\CoreBundle\Ckeditor\CkeditorConfiguration for example.')
                     ->example(['my_custom_config' => CkeditorConfiguration::EXAMPLE_CONFIG])
-                    ->normalizeKeys(false)
                     ->useAttributeAsKey('name')
-                    ->arrayPrototype()
-                        ->scalarPrototype()->end()
+                    ->normalizeKeys(false)
+                    ->variablePrototype()
                     ->end();
     }