diff --git a/novaclient/v1_1/shell.py b/novaclient/v1_1/shell.py
index 77ad1986e..d8260cc89 100644
--- a/novaclient/v1_1/shell.py
+++ b/novaclient/v1_1/shell.py
@@ -1787,11 +1787,11 @@ def do_volume_update(cs, args):
     help=_('Name or ID of server.'))
 @utils.arg('attachment_id',
     metavar='<volume>',
-    help=_('Attachment ID of the volume.'))
+    help=_('ID of the volume to detach.'))
 def do_volume_detach(cs, args):
     """Detach a volume from a server."""
     cs.volumes.delete_server_volume(_find_server(cs, args.server).id,
-                                        args.attachment_id)
+                                    args.attachment_id)
 
 
 @utils.service_type('volume')
diff --git a/novaclient/v3/shell.py b/novaclient/v3/shell.py
index 35177122e..8e8f575e7 100644
--- a/novaclient/v3/shell.py
+++ b/novaclient/v3/shell.py
@@ -1463,11 +1463,11 @@ def do_volume_update(cs, args):
     help='Name or ID of server.')
 @utils.arg('attachment_id',
     metavar='<volume>',
-    help='Attachment ID of the volume.')
+    help='ID of the volume to detach.')
 def do_volume_detach(cs, args):
     """Detach a volume from a server."""
     cs.volumes.delete_server_volume(_find_server(cs, args.server).id,
-                                        args.attachment_id)
+                                    args.attachment_id)
 
 
 @utils.arg('server', metavar='<server>', help='Name or ID of server.')