diff --git a/src/Plugin/Block/FacetBlock.php b/src/Plugin/Block/FacetBlock.php
index 849d0df..c353e0b 100644
--- a/src/Plugin/Block/FacetBlock.php
+++ b/src/Plugin/Block/FacetBlock.php
@@ -10,6 +10,7 @@ namespace Drupal\facets\Plugin\Block;
 use Drupal\Core\Block\BlockBase;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Plugin\PluginBase;
 use Drupal\facets\FacetManager\DefaultFacetManager;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
@@ -24,7 +25,7 @@ use Symfony\Component\DependencyInjection\ContainerInterface;
 class FacetBlock extends BlockBase implements ContainerFactoryPluginInterface {
 
   /**
-   * The facet_manager plugin manager.
+   * The facet manager service.
    *
    * @var DefaultFacetManager
    */
@@ -67,12 +68,13 @@ class FacetBlock extends BlockBase implements ContainerFactoryPluginInterface {
    * {@inheritdoc}
    */
   public function build() {
-    /** @var \Drupal\facets\FacetInterface $facet */
-    $facet_mapping = $this->configuration['id'];
-    $facet_id = explode(':', $facet_mapping)[1];
-
     $em = \Drupal::getContainer()->get('entity_type.manager');
 
+    // The id saved in the configuration is in the format of
+    // base_plugin:facet_id. We're splitting that to get to the facet id.
+    $facet_mapping = $this->configuration['id'];
+    $facet_id = explode(PluginBase::DERIVATIVE_SEPARATOR, $facet_mapping)[1];
+
     /** @var \Drupal\facets\FacetInterface $facet */
     $facet = $em->getStorage('facets_facet')->load($facet_id);
 
@@ -109,11 +111,13 @@ class FacetBlock extends BlockBase implements ContainerFactoryPluginInterface {
    * {@inheritdoc}
    */
   public function calculateDependencies() {
-    $facet_mapping = $this->configuration['id'];
-    $facet_id = explode(':', $facet_mapping)[1];
-
     $em = \Drupal::getContainer()->get('entity_type.manager');
 
+    // The id saved in the configuration is in the format of
+    // base_plugin:facet_id. We're splitting that to get to the facet id.
+    $facet_mapping = $this->configuration['id'];
+    $facet_id = explode(PluginBase::DERIVATIVE_SEPARATOR, $facet_mapping)[1];
+
     /** @var \Drupal\facets\FacetInterface $facet */
     $facet = $em->getStorage('facets_facet')->load($facet_id);
     $config_name = $facet->getConfigDependencyName();
diff --git a/src/Plugin/Block/FacetBlockDeriver.php b/src/Plugin/Block/FacetBlockDeriver.php
index a082946..e410f3d 100644
--- a/src/Plugin/Block/FacetBlockDeriver.php
+++ b/src/Plugin/Block/FacetBlockDeriver.php
@@ -13,7 +13,7 @@ use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
- * Provides a 'FacetBlock' block.
+ * This deriver creates a block for every facet that has been created.
  */
 class FacetBlockDeriver implements ContainerDeriverInterface {
 
@@ -27,9 +27,11 @@ class FacetBlockDeriver implements ContainerDeriverInterface {
   protected $derivatives = array();
 
   /**
+   * The entity storage used for facets.
+   *
    * @var \Drupal\Core\Entity\EntityStorageInterface $facetStorage
    */
-  public $facetStorage;
+  protected $facetStorage;
 
   /**
    * {@inheritdoc}
@@ -57,11 +59,11 @@ class FacetBlockDeriver implements ContainerDeriverInterface {
     $base_plugin_id = $base_plugin_definition['id'];
 
     if (!isset($this->derivatives[$base_plugin_id])) {
-
       $plugin_derivatives = array();
+
+      /** @var \Drupal\facets\FacetInterface[] $all_facets */
       $all_facets = $this->facetStorage->loadMultiple();
 
-      /** @var \Drupal\facets\FacetInterface $facet */
       foreach ($all_facets as $facet) {
         $machine_name = $facet->id();
 
@@ -73,7 +75,6 @@ class FacetBlockDeriver implements ContainerDeriverInterface {
         ] + $base_plugin_definition;
 
         $sources[] = $this->t('Facet: :facet', [':facet' => $facet->getName()]);
-
       }
 
       $this->derivatives[$base_plugin_id] = $plugin_derivatives;