terraform-provider-aws: Microsoft AD Size ignored

Hi there,

Terraform Version

Terraform v0.10.7

Affected Resource(s)

aws_directory_service_directory

Terraform Configuration Files

resource "aws_directory_service_directory" "active-directory" {
  name     = "${var.name}"
  password = "${var.password}"
  type     = "MicrosoftAD"
  size     = "Small"

  vpc_settings {
    vpc_id     = "${var.vpc_id}"
    subnet_ids = ["${var.subnet1}", "${var.subnet2}"]
  }
}

Expected Behavior

I would expect a Microsoft AD to be created on AWS with a Size of Standard

Actual Behavior

Microsoft AD is created with a Size of Enterprise

Steps to Reproduce

1. terraform apply