diff --git a/docs/resources/aws_cost_credentials.md b/docs/resources/aws_cost_credentials.md
index d8500363..f91af3a5 100644
--- a/docs/resources/aws_cost_credentials.md
+++ b/docs/resources/aws_cost_credentials.md
@@ -20,6 +20,10 @@ description: |-
 - `arn` (String) the aws role arn
 - `name` (String) the name for the credentials
 
+### Optional
+
+- `duration` (Number) the session duration in seconds. If set must be one of the following: 3600 (1h), 7200 (2h), 14400 (4h), 18000 (5h default), 28800 (8h), 43200 (12h)
+
 ### Read-Only
 
 - `id` (String) The ID of this resource.