There is a button on the customer list page and details page called generate from template. This can be quite handy to use if you want to populate some data into an external Word document for example. Like a customer letter. There are a few things that you will need to do to configure this button to show your templates.
First configure a query type document data source as this will allow you to build a template in Word using the Office-Addin. Second save that template to a repository like SharePoint. Third configure the document type to activate the template.
Here is a quick example.
AX2012 R3 CU11