Add more detail to this Role's documentation.

roles/ndfc_vrf_replaced/README.md

@@ -1,22 +1,48 @@
 # ndfc_vrf_replaced
 
-Update VRF using Ansible state: replaced
+Replace vrf ``vrf_name`` in fabric ``fabric_name`` with the current user-defined parameters.
 
-### Requirements
+### Role Variables
 
-None
+Variable        | Type  | Description
+----------------|-------|----------------------------------------
+fabric_name     | str() | The fabric in which ``vrf_name`` resides
+vrf_name        | str() | The vrf to update
 
-### Role Variables
+Fabric and vrf parameters, including ``fabric_name`` and ``vrf_name``, are defined in the following file:
+
+``./roles/ndfc_common/vars/main.yml``
+
+Specifically, vrfs are defined in the ``vrfs`` list in the above file.  User-defined parameters include:
 
-fabric_name: The name of the fabric in which the VRF resides.  This will typically be defined in the playbook's vars: section.
-vrfs: A list of dict containing NDFC vrf configuration. See vrfs list of dict in ~/ndfc_common/vars/main.yml
+Variable               | Example        | Type         | Description
+-----------------------|----------------|--------------|-------------------
+fabric                 | f1             | str()        | Fabric in which network resides
+vrf_name               | vrf_1          | str()        | vrf in which network resides
+vrf_id                 | 9003031        | int()        | vrf Layer3 VNI / vn-segment
+vlan_id                | 3031           | int()        | vrf associated vlan 
+vrf_template           | TemplateVrf    | str()        | Overlay VRF Template For Leafs
+vrf_extension_template | TemplateExVrf  | str()        | Overlay VRF Template For Borders
+service_vrf_template   | ServiceVrf     | str()        | Service vrf template
+attach                 | See example    | list of dict | List of mgmt0 ip addresses of switches on which the VRF is configured
+attach.ip_address      | 192.168.1.1    | IP address   | mgmt0 address of the switch to which the vrf is attached
 
+See the following for details:
 
-### Dependencies
+[./roles/ndfc_common/README.md](https://github.com/allenrobel/ndfc-roles/tree/master/roles/ndfc_common/README.md)
 
 ## Example Playbook
 
-example_ndfc_vrf_replaced.yml
+```yaml
+---
+- hosts: ndfc
+  gather_facts: false
+  roles:
+    - ndfc_vrf_replaced
+  vars:
+    fabric_name: f1
+    vrf_name: v2
+```
 
 ### License