diff --git a/iam-policy-documents.tf b/iam-policy-documents.tf
index d89bc34..0e643f2 100644
--- a/iam-policy-documents.tf
+++ b/iam-policy-documents.tf
@@ -38,7 +38,7 @@ data "aws_iam_policy_document" "backend_assume_role_restricted" {
 
     principals {
       type        = "AWS"
-      identifiers = "${length(each.value) > 0 ? each.value : list(data.aws_caller_identity.current.account_id)}"
+      identifiers = length(each.value) > 0 ? each.value : list(data.aws_caller_identity.current.account_id)
     }
   }
 }
diff --git a/iam.tf b/iam.tf
index 3d6c36b..c60fb8a 100644
--- a/iam.tf
+++ b/iam.tf
@@ -20,7 +20,7 @@ resource "aws_iam_role" "backend_restricted" {
 
   name               = "${var.resource_prefix}-terraform-backend-${each.key}"
   description        = "Allows access to the ${each.key} workspace prefix"
-  assume_role_policy = data.aws_iam_policy_document.backend_assume_role_restricted["${each.key}"].json
+  assume_role_policy = data.aws_iam_policy_document.backend_assume_role_restricted[each.key].json
   tags               = var.tags
 }
 
@@ -28,7 +28,7 @@ resource "aws_iam_role_policy" "backend_restricted" {
   for_each = var.workspace_details
 
   name   = "${var.resource_prefix}-terraform-backend-${each.key}"
-  policy = data.aws_iam_policy_document.iam_role_policy_restricted["${each.key}"].json
+  policy = data.aws_iam_policy_document.iam_role_policy_restricted[each.key].json
   role   = "${var.resource_prefix}-terraform-backend-${each.key}"
 
   depends_on = [aws_iam_role.backend_restricted]