Changing cultural mindset on mapping processes

I am interested in receiving feedback on how to implement the use of process maps throughout an organization. My office has done a great job and we have process maps for every action – these have helped greatly with new hires and we constantly review for changes resulting in higher efficiencies. Other offices within our organization give me that hazey “what are you talking about” look when process maps are mentioned. Many of them simply store that information in their heads and rely on SOPs. Whether it be process maps or another tool, my intent is to ensure all offices have documented steps detailing the tasks associated with their functions-preventing loss of intellectual property when an employee leaves and promoting process improvement. Would love to hear ideas from all willing to share and thank you in advance.