This template will create a DocumentDB Database Account with the name provided, the location set to the same location as the resource group that was used, and the Offer Type set to Standard.
This template includes the optional Consistency Policy property, the account will be created with the default consistency level specified.
For more information on DocumentDB Consistency Levels please refer to, Using consistency levels to maximize availability and performance in DocumentDB
If you want just want to create a DocumentDB with the default values set then refer to, 101-create-documentdb-account to see how it is done.