docs: updated README

README.md

@@ -636,6 +636,7 @@ No modules.
 | <a name="output_nat_ids"></a> [nat\_ids](#output\_nat\_ids) | List of allocation ID of Elastic IPs created for AWS NAT Gateway |
 | <a name="output_nat_public_ips"></a> [nat\_public\_ips](#output\_nat\_public\_ips) | List of public Elastic IPs created for AWS NAT Gateway |
 | <a name="output_natgw_ids"></a> [natgw\_ids](#output\_natgw\_ids) | List of NAT Gateway IDs |
+| <a name="output_natgw_interface_ids"></a> [natgw\_interface\_ids](#output\_natgw\_interface\_ids) | List of Network Interface IDs assigned to NAT Gateways |
 | <a name="output_outpost_network_acl_arn"></a> [outpost\_network\_acl\_arn](#output\_outpost\_network\_acl\_arn) | ARN of the outpost network ACL |
 | <a name="output_outpost_network_acl_id"></a> [outpost\_network\_acl\_id](#output\_outpost\_network\_acl\_id) | ID of the outpost network ACL |
 | <a name="output_outpost_subnet_arns"></a> [outpost\_subnet\_arns](#output\_outpost\_subnet\_arns) | List of ARNs of outpost subnets |