diff --git a/laravel/database/eloquent/relationships/has_many_and_belongs_to.php b/laravel/database/eloquent/relationships/has_many_and_belongs_to.php
index 1c0d3e03..7dc8b0a3 100644
--- a/laravel/database/eloquent/relationships/has_many_and_belongs_to.php
+++ b/laravel/database/eloquent/relationships/has_many_and_belongs_to.php
@@ -121,6 +121,7 @@ public function detach($ids)
 	public function sync($ids)
 	{
 		$current = $this->pivot()->lists($this->other_key());
+		$ids = (array) $ids;
 
 		// First we need to attach any of the associated models that are not currently
 		// in the joining table. We'll spin through the given IDs, checking to see
@@ -140,7 +141,7 @@ public function sync($ids)
 
 		if (count($detach) > 0)
 		{
-			$this->detach(array_diff($current, $ids));
+			$this->detach($detach);
 		}
 	}