diff --git a/README.md b/README.md
index 86fb626..5f74e68 100644
--- a/README.md
+++ b/README.md
@@ -433,6 +433,7 @@ components:
 | <a name="output_master_hostname"></a> [master\_hostname](#output\_master\_hostname) | Postgres master hostname |
 | <a name="output_reader_endpoint"></a> [reader\_endpoint](#output\_reader\_endpoint) | Postgres reader endpoint |
 | <a name="output_replicas_hostname"></a> [replicas\_hostname](#output\_replicas\_hostname) | Postgres replicas hostname |
+| <a name="output_security_group_id"></a> [security\_group\_id](#output\_security\_group\_id) | The security group ID of the Aurora Postgres cluster |
 | <a name="output_ssm_key_paths"></a> [ssm\_key\_paths](#output\_ssm\_key\_paths) | Names (key paths) of all SSM parameters stored for this cluster |
 <!-- markdownlint-restore -->
 
diff --git a/src/README.md b/src/README.md
index 8340b96..f9ddef2 100644
--- a/src/README.md
+++ b/src/README.md
@@ -381,6 +381,7 @@ components:
 | <a name="output_master_hostname"></a> [master\_hostname](#output\_master\_hostname) | Postgres master hostname |
 | <a name="output_reader_endpoint"></a> [reader\_endpoint](#output\_reader\_endpoint) | Postgres reader endpoint |
 | <a name="output_replicas_hostname"></a> [replicas\_hostname](#output\_replicas\_hostname) | Postgres replicas hostname |
+| <a name="output_security_group_id"></a> [security\_group\_id](#output\_security\_group\_id) | The security group ID of the Aurora Postgres cluster |
 | <a name="output_ssm_key_paths"></a> [ssm\_key\_paths](#output\_ssm\_key\_paths) | Names (key paths) of all SSM parameters stored for this cluster |
 <!-- markdownlint-restore -->