I agree with Graham and regularly make use of his Add-In.


You could simply use the "Company" Document Property Content Control that comes installed in Word under Insert > Quick Parts > Document Property or repurpose one of the others. These are built-in mapped document properties.


Repeating Data Using Document Property Content Controls and Other Mapped Content Controls

A custom mapped content control will also work fine.


To me, this is the simplest and most automatic method of repeating data. There are others, though, as well: Repeating Data (Populating Multiple Like Fields) by Greg Maxey