This shows a detailed view of a single item.
A detail block has no properties. The object on the block is used for Block access control as normal but it also doubles up as the data provider for the detail item. It is then assumed that the object returns a single database row when the block applies the object Id restriction that joins on the page keys.
The object should include both the primary keys of the object and the properties required to display the detail item. This will include the item's type together with that item's specific properties.
For details of available items and the properties that can be set for each please refer to Item templates.