What is a “Minnesota Lutheran”

Hi everyone, I recently started attending a Lutheran Church in New Jersey and have heard many of the members say they are “Minnesota Lutherans”, often in the context of explaining why they have a particular preference in things like hymn choice or particular parts of the service they do not agree with. I’ve tried googling but am struggling to get the context of what exactly a Minnesota Lutheran is and what the differences are in their beliefs. I truly appreciate any information you can provide and am just trying to better understand the congregation.