diff --git a/django/contrib/admin/views/doc.py b/django/contrib/admin/views/doc.py
index 166ecdff2dd..e4d0f1c6488 100644
--- a/django/contrib/admin/views/doc.py
+++ b/django/contrib/admin/views/doc.py
@@ -288,9 +288,9 @@ DATA_TYPE_MAPPING = {
 
 def get_readable_field_data_type(field):
     # ForeignKey is a special case. Use the field type of the relation.
-    if field.__class__.__name__ == 'ForeignKey':
+    if field.get_internal_type() == 'ForeignKey':
         field = field.rel.get_related_field()
-    return DATA_TYPE_MAPPING[field.__class__.__name__] % field.__dict__
+    return DATA_TYPE_MAPPING[field.get_internal_type()] % field.__dict__
 
 def extract_views_from_urlpatterns(urlpatterns, base=''):
     """